diff --git a/Cargo.toml b/Cargo.toml
index 996897f2..131907e7 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,7 +20,6 @@ opt-level = 0
 opt-level = 3
 
 [workspace.dependencies]
-# TODO: uncomment and correct version `version = "~0.0.1"`
 document-features = "0.2.10"
 fastsim-core = { path = "fastsim-core" }
 anyhow = "1.0.71"
diff --git a/benchmarks/f3-save-int-1.py b/benchmarks/f3-save-int-1.py
index d57a94f2..234ccbbe 100755
--- a/benchmarks/f3-save-int-1.py
+++ b/benchmarks/f3-save-int-1.py
@@ -4,10 +4,7 @@
 
 @profile(precision=3)
 def build_and_run_sim_drive():
-    veh = fsim.Vehicle.from_file(
-        # TODO: figure out why `str` is needed here
-        str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
-    )
+    veh = fsim.Vehicle.from_resource("2012_Ford_Fusion.yaml")
     fsim.set_param_from_path(veh, "save_interval", 1)
     cyc = fsim.Cycle.from_resource("udds.csv")
     sd = fsim.SimDrive(veh, cyc)
@@ -23,8 +20,8 @@ def build_and_run_sim_drive():
      # 5   61.562 MiB   61.562 MiB           1   @profile(precision=3)
      # 6                                         def build_and_run_sim_drive():
      # 7   62.125 MiB    0.562 MiB           2       veh = fsim.Vehicle.from_file(
-     # 8                                                 # TODO: figure out why `str` is needed here
-     # 9   61.562 MiB    0.000 MiB           1           str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
+     # 8                                                 
+     # 9   61.562 MiB    0.000 MiB           1           fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml"
     # 10                                             )
     # 11   62.125 MiB    0.000 MiB           1       veh.save_interval = 1
     # 12   62.312 MiB    0.188 MiB           1       cyc = fsim.Cycle.from_resource("udds.csv")
diff --git a/benchmarks/f3-save-int-none.py b/benchmarks/f3-save-int-none.py
index d260e493..a89efc43 100755
--- a/benchmarks/f3-save-int-none.py
+++ b/benchmarks/f3-save-int-none.py
@@ -4,10 +4,7 @@
 
 @profile(precision=3)
 def build_and_run_sim_drive():
-    veh = fsim.Vehicle.from_file(
-        # TODO: figure out why `str` is needed here
-        str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
-    )
+    veh = fsim.Vehicle.from_resource("2012_Ford_Fusion.yaml")
     fsim.set_param_from_path(veh, "save_interval", None)
     cyc = fsim.Cycle.from_resource("udds.csv")
     sd = fsim.SimDrive(veh, cyc)
@@ -23,8 +20,8 @@ def build_and_run_sim_drive():
 #      5   61.203 MiB   61.203 MiB           1   @profile(precision=3)
 #      6                                         def build_and_run_sim_drive():
 #      7   61.766 MiB    0.562 MiB           2       veh = fsim.Vehicle.from_file(
-#      8                                                 # TODO: figure out why `str` is needed here
-#      9   61.203 MiB    0.000 MiB           1           str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
+#      8                                                 
+#      9   61.203 MiB    0.000 MiB           1           fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml"
 #     10                                             )
 #     11   61.766 MiB    0.000 MiB           1       veh.save_interval = None
 #     12   61.938 MiB    0.172 MiB           1       cyc = fsim.Cycle.from_resource("udds.csv")
diff --git a/fastsim-core/fastsim-proc-macros/src/cumu_method_derive.rs b/fastsim-core/fastsim-proc-macros/src/cumu_method_derive.rs
index abc39f8d..356dd5f1 100644
--- a/fastsim-core/fastsim-proc-macros/src/cumu_method_derive.rs
+++ b/fastsim-core/fastsim-proc-macros/src/cumu_method_derive.rs
@@ -1,7 +1,5 @@
 use crate::imports::*;
 
-// TODO: make sure this macro is propagated and implementd everywhere it's needed
-
 pub(crate) fn cumu_method_derive(input: TokenStream) -> TokenStream {
     let item_struct = syn::parse_macro_input!(input as syn::ItemStruct);
     let ident = &item_struct.ident;
diff --git a/fastsim-core/fastsim-proc-macros/src/cycle_derive.rs b/fastsim-core/fastsim-proc-macros/src/cycle_derive.rs
index 07faf193..cfb3412d 100644
--- a/fastsim-core/fastsim-proc-macros/src/cycle_derive.rs
+++ b/fastsim-core/fastsim-proc-macros/src/cycle_derive.rs
@@ -53,7 +53,7 @@ pub(crate) fn cycle_derive(input: TokenStream) -> TokenStream {
         .unwrap();
     generated.append_all(quote! {
         #[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
-        #[pyo3_api(
+        #[fastsim_api(
             #[pyo3(name = "len")]
             fn len_py(&self) -> usize {
                 self.len()
diff --git a/fastsim-core/fastsim-proc-macros/src/pyo3_api.rs b/fastsim-core/fastsim-proc-macros/src/fastsim_api.rs
similarity index 99%
rename from fastsim-core/fastsim-proc-macros/src/pyo3_api.rs
rename to fastsim-core/fastsim-proc-macros/src/fastsim_api.rs
index 9687fcc1..5950ae3a 100644
--- a/fastsim-core/fastsim-proc-macros/src/pyo3_api.rs
+++ b/fastsim-core/fastsim-proc-macros/src/fastsim_api.rs
@@ -1,9 +1,9 @@
 use crate::imports::*;
-mod pyo3_api_utils;
+mod fastsim_api_utils;
 use crate::utilities::parse_ts_as_fn_defs;
-use pyo3_api_utils::*;
+use fastsim_api_utils::*;
 
-pub(crate) fn pyo3_api(attr: TokenStream, item: TokenStream) -> TokenStream {
+pub(crate) fn fastsim_api(attr: TokenStream, item: TokenStream) -> TokenStream {
     let mut ast = syn::parse_macro_input!(item as syn::ItemStruct);
     let ident = &ast.ident;
     // println!("{}", String::from("*").repeat(30));
diff --git a/fastsim-core/fastsim-proc-macros/src/pyo3_api/pyo3_api_utils.rs b/fastsim-core/fastsim-proc-macros/src/fastsim_api/fastsim_api_utils.rs
similarity index 91%
rename from fastsim-core/fastsim-proc-macros/src/pyo3_api/pyo3_api_utils.rs
rename to fastsim-core/fastsim-proc-macros/src/fastsim_api/fastsim_api_utils.rs
index d26630d3..52034b80 100644
--- a/fastsim-core/fastsim-proc-macros/src/pyo3_api/pyo3_api_utils.rs
+++ b/fastsim-core/fastsim-proc-macros/src/fastsim_api/fastsim_api_utils.rs
@@ -207,35 +207,34 @@ fn extract_type_path(ty: &syn::Type) -> Option<&syn::Path> {
     }
 }
 
-#[allow(unused)]
 /// adapted from https://stackoverflow.com/questions/55271857/how-can-i-get-the-t-from-an-optiont-when-using-syn
 fn extract_type_from_option(ty: &syn::Type) -> Option<&syn::Type> {
-    use syn::{GenericArgument, Path, PathArguments, PathSegment};
-
-    // TODO store (with lazy static) the vec of string
-    // TODO maybe optimization, reverse the order of segments
-    fn extract_option_segment(path: &Path) -> Option<&PathSegment> {
-        let idents_of_path = path.segments.iter().fold(String::new(), |mut acc, v| {
-            acc.push_str(&v.ident.to_string());
-            acc.push('|');
-            acc
-        });
-        vec!["Option|", "std|option|Option|", "core|option|Option|"]
-            .into_iter()
-            .find(|s| idents_of_path == *s)
-            .and_then(|_| path.segments.last())
+    fn extract_option_argument(path: &Path) -> Option<&GenericArgument> {
+        let mut ident_path = String::new();
+        for segment in &path.segments {
+            ident_path.push_str(&segment.ident.to_string());
+
+            // Exit when the inner brackets are found
+            match &segment.arguments {
+                syn::PathArguments::AngleBracketed(params) => {
+                    return match ident_path.as_str() {
+                        "Option" | "std::option::Option" | "core::option::Option" => {
+                            params.args.first()
+                        }
+                        _ => None,
+                    };
+                }
+                syn::PathArguments::None => {}
+                _ => return None,
+            }
+
+            ident_path.push_str("::");
+        }
+        None
     }
 
     extract_type_path(ty)
-        .and_then(extract_option_segment)
-        .and_then(|path_seg| {
-            let type_params = &path_seg.arguments;
-            // It should have only on angle-bracketed param ("<String>"):
-            match *type_params {
-                PathArguments::AngleBracketed(ref params) => params.args.first(),
-                _ => None,
-            }
-        })
+        .and_then(extract_option_argument)
         .and_then(|generic_arg| match *generic_arg {
             GenericArgument::Type(ref ty) => Some(ty),
             _ => None,
@@ -310,11 +309,9 @@ pub(crate) fn impl_getters_and_setters(
     let mut vec_layers: u8 = 0;
     let mut inner_type = &ftype;
 
-    // TODO: figure this out and uncomment.  Then check that all `Option` fields are handled appropriately.
-    // pull out `inner_type` from `Option<inner_type>`
-    // if let Some(opt_inner_type) = extract_type_from_option(inner_type) {
-    //     inner_type = opt_inner_type;
-    // }
+    if let Some(opt_inner_type) = extract_type_from_option(inner_type) {
+        inner_type = opt_inner_type;
+    }
 
     // pull out `inner_type` from `Vec<inner_type>`, recursively if there is any nesting
     while let Some(vec_inner_type) = extract_type_from_vec(inner_type) {
@@ -346,6 +343,7 @@ pub(crate) fn impl_getters_and_setters(
             "Mass" => extract_units!(uom::si::mass::kilogram),
             "MomentOfInertia" => extract_units!(uom::si::moment_of_inertia::kilogram_square_meter),
             "Power" => extract_units!(uom::si::power::watt),
+            "SpecificPower" => extract_units!(uom::si::specific_power::watt_per_kilogram),
             "PowerRate" => extract_units!(uom::si::power_rate::watt_per_second),
             "Pressure" => extract_units!(uom::si::pressure::kilopascal, uom::si::pressure::bar),
             "Ratio" => extract_units!(uom::si::ratio::ratio),
diff --git a/fastsim-core/fastsim-proc-macros/src/history_vec_derive.rs b/fastsim-core/fastsim-proc-macros/src/history_vec_derive.rs
index 94591e1b..8f19e6b6 100644
--- a/fastsim-core/fastsim-proc-macros/src/history_vec_derive.rs
+++ b/fastsim-core/fastsim-proc-macros/src/history_vec_derive.rs
@@ -58,7 +58,7 @@ pub(crate) fn history_vec_derive(input: TokenStream) -> TokenStream {
         .unwrap();
     generated.append_all(quote! {
         #[derive(Clone, Debug, Serialize, Deserialize, PartialEq)]
-        #[pyo3_api(
+        #[fastsim_api(
             #[pyo3(name = "len")]
             fn len_py(&self) -> usize {
                 self.len()
diff --git a/fastsim-core/fastsim-proc-macros/src/imports.rs b/fastsim-core/fastsim-proc-macros/src/imports.rs
index d83ad604..0368a86d 100644
--- a/fastsim-core/fastsim-proc-macros/src/imports.rs
+++ b/fastsim-core/fastsim-proc-macros/src/imports.rs
@@ -3,4 +3,6 @@ pub(crate) use proc_macro2::TokenStream as TokenStream2;
 pub(crate) use proc_macro_error::{abort, abort_call_site, emit_error, proc_macro_error};
 pub(crate) use quote::{quote, ToTokens, TokenStreamExt}; // ToTokens is implicitly used as a trait
 pub(crate) use regex::Regex;
-pub(crate) use syn::{spanned::Spanned, Ident, MetaNameValue, Meta, NestedMeta};
+pub(crate) use syn::{
+    spanned::Spanned, GenericArgument, Ident, Meta, MetaNameValue, NestedMeta, Path,
+};
diff --git a/fastsim-core/fastsim-proc-macros/src/lib.rs b/fastsim-core/fastsim-proc-macros/src/lib.rs
index a101d4c0..d0909d20 100644
--- a/fastsim-core/fastsim-proc-macros/src/lib.rs
+++ b/fastsim-core/fastsim-proc-macros/src/lib.rs
@@ -2,9 +2,9 @@ mod imports;
 use imports::*;
 mod cumu_method_derive;
 mod cycle_derive;
+mod fastsim_api;
 mod history_vec_derive;
 mod hm_derive;
-mod pyo3_api;
 mod timer;
 mod utilities;
 
@@ -12,8 +12,8 @@ mod utilities;
 #[proc_macro_attribute]
 /// macro for creating appropriate setters and getters for pyo3 struct attributes
 /// and other, non-python API functionality
-pub fn pyo3_api(attr: TokenStream, item: TokenStream) -> TokenStream {
-    pyo3_api::pyo3_api(attr, item)
+pub fn fastsim_api(attr: TokenStream, item: TokenStream) -> TokenStream {
+    fastsim_api::fastsim_api(attr, item)
 }
 
 #[proc_macro_error]
diff --git a/fastsim-core/resources/vehicles/2012_Ford_Fusion.yaml b/fastsim-core/resources/vehicles/2012_Ford_Fusion.yaml
index 87cd0124..6d152f84 100644
--- a/fastsim-core/resources/vehicles/2012_Ford_Fusion.yaml
+++ b/fastsim-core/resources/vehicles/2012_Ford_Fusion.yaml
@@ -8,8 +8,8 @@ pt_type:
       pwr_ramp_lag_seconds: 1.0
       energy_capacity_joules: 2124000000.0
     fc:
-      mass: ~
-      specific_pwr: ~
+      mass_kilograms: ~
+      specific_pwr_watts_per_kilogram: ~
       pwr_out_max_watts: 130500.0
       pwr_out_max_init_watts: 21750.0
       pwr_ramp_lag_seconds: 6.0
@@ -53,13 +53,13 @@ chassis:
   wheel_rr_coef: 0.007
   wheel_inertia_kilogram_square_meters: 0.82
   num_wheels: 4
-  wheel_radius: 0.326
+  wheel_radius_meters: 0.326
   cg_height_meters: 0.53
   wheel_fric_coef: 0.7
   drive_type: FWD
   drive_axle_weight_frac: 0.59
   wheel_base_meters: 2.72
-mass: 1644.2724500334996
+mass_kilograms: 1644.2724500334996
 pwr_aux_watts: 700.0
 trans_eff: 0.875
 save_interval: 1
diff --git a/tests/assets/2016_TOYOTA_Prius_Two.yaml b/fastsim-core/resources/vehicles/2016_TOYOTA_Prius_Two.yaml
similarity index 88%
rename from tests/assets/2016_TOYOTA_Prius_Two.yaml
rename to fastsim-core/resources/vehicles/2016_TOYOTA_Prius_Two.yaml
index 24dd4df8..a6891492 100644
--- a/tests/assets/2016_TOYOTA_Prius_Two.yaml
+++ b/fastsim-core/resources/vehicles/2016_TOYOTA_Prius_Two.yaml
@@ -4,8 +4,8 @@ year: 2016
 pt_type:
   HybridElectricVehicle:
     res:
-      mass: ~
-      specific_energy: ~
+      mass_kilograms: ~
+      specific_energy_joules_per_kilogram: ~
       pwr_out_max_watts: 100000.0
       energy_capacity_joules: 2700000.0
       min_soc: 0.25
@@ -16,8 +16,8 @@ pt_type:
       pwr_ramp_lag_seconds: 1.1
       energy_capacity_joules: 1392840000.0
     fc:
-      mass: ~
-      specific_pwr: ~
+      mass_kilograms: ~
+      specific_pwr_watts_per_kilogram: ~
       pwr_out_max_watts: 71000.0
       pwr_out_max_init_watts: 11639.344262295082
       pwr_ramp_lag_seconds: 6.1
@@ -79,8 +79,8 @@ pt_type:
         - 0.93
         - 0.92
       pwr_out_max_watts: 53000.0
-      specific_pwr: ~
-      mass: ~
+      specific_pwr_watts_per_kilogram: ~
+      mass_kilograms: ~
       save_interval: 1
     hev_controls: RESGreedy
     mass: ~
@@ -90,13 +90,13 @@ chassis:
   wheel_rr_coef: 0.0064
   wheel_inertia_kilogram_square_meters: 0.815
   num_wheels: 4
-  wheel_radius: 0.3175
+  wheel_radius_meters: 0.3175
   cg_height_meters: 0.53
   wheel_fric_coef: 0.7
   drive_type: FWD
   drive_axle_weight_frac: 0.59
   wheel_base_meters: 2.7
-mass: 1635.0
+mass_kilograms: 1635.0
 pwr_aux_watts: 1050.0
 trans_eff: 0.98
 save_interval: 1
diff --git a/fastsim-core/src/bin/f3-2012-ford-fusion-udds.rs b/fastsim-core/src/bin/f3-2012-ford-fusion-udds.rs
index 8e277ac8..08d9d49d 100644
--- a/fastsim-core/src/bin/f3-2012-ford-fusion-udds.rs
+++ b/fastsim-core/src/bin/f3-2012-ford-fusion-udds.rs
@@ -1,4 +1,4 @@
-/// Binary for running the 2012 Ford Fusion in fastsim-3 with `cargo build
+/// Binary for profiling the 2012 Ford Fusion in fastsim-3 with `cargo build
 /// --profile profiling  --bin f3-2012-ford-fusion-udds`.  To run this for
 /// profiling, install [samply] (https://github.com/mstange/samply) and then run
 /// `samply record ./target/profiling/f3-2012-ford-fusion-udds`
diff --git a/fastsim-core/src/drive_cycle.rs b/fastsim-core/src/drive_cycle.rs
index c1ec1b98..1b6e452a 100644
--- a/fastsim-core/src/drive_cycle.rs
+++ b/fastsim-core/src/drive_cycle.rs
@@ -1,7 +1,7 @@
 use crate::imports::*;
 use fastsim_2::cycle::RustCycle as Cycle2;
 
-#[pyo3_api(
+#[fastsim_api(
     fn __len__(&self) -> usize {
         self.len()
     }
@@ -372,7 +372,7 @@ impl Cycle {
     }
 }
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Default, Debug, Serialize, Deserialize, PartialEq, Clone)]
 /// Element of `Cycle`.  Used for vec-like operations.
 pub struct CycleElement {
@@ -382,12 +382,12 @@ pub struct CycleElement {
     /// simulation power \[W\]
     #[serde(alias = "speed_mps", alias = "cycMps")]
     speed: si::Velocity,
-    // TODO: make `pyo3_api` handle Option or write custom getter/setter
+    // TODO: make `fastsim_api` handle Option or write custom getter/setter
     #[api(skip_get, skip_set)]
     /// road grade
     #[serde(skip_serializing_if = "Option::is_none", alias = "cycGrade")]
     pub grade: Option<si::Ratio>,
-    // TODO: make `pyo3_api` handle Option or write custom getter/setter
+    // TODO: make `fastsim_api` handle Option or write custom getter/setter
     #[api(skip_get, skip_set)]
     /// road charging/discharing capacity
     pub pwr_max_charge: Option<si::Power>,
diff --git a/fastsim-core/src/imports.rs b/fastsim-core/src/imports.rs
index cf6d7f16..27fa19ff 100644
--- a/fastsim-core/src/imports.rs
+++ b/fastsim-core/src/imports.rs
@@ -16,7 +16,9 @@ pub(crate) use crate::utils::{
 pub(crate) use crate::utils::{Pyo3Vec2Wrapper, Pyo3Vec3Wrapper, Pyo3VecWrapper};
 pub(crate) use derive_more::IsVariant;
 pub(crate) use eng_fmt::FormatEng;
-pub(crate) use fastsim_proc_macros::{pyo3_api, HistoryMethods, HistoryVec, SetCumulative, timer};
+pub(crate) use fastsim_proc_macros::{
+    fastsim_api, timer, HistoryMethods, HistoryVec, SetCumulative,
+};
 
 pub(crate) use anyhow::{anyhow, bail, ensure, Context};
 pub(crate) use duplicate::duplicate_item;
diff --git a/fastsim-core/src/simdrive.rs b/fastsim-core/src/simdrive.rs
index 95a1ec1d..2ad33dd7 100644
--- a/fastsim-core/src/simdrive.rs
+++ b/fastsim-core/src/simdrive.rs
@@ -5,14 +5,14 @@ use super::vehicle::Vehicle;
 use crate::air_properties as air;
 use crate::imports::*;
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Clone, Debug, Deserialize, Serialize, PartialEq, HistoryMethods)]
 /// Solver parameters
 pub struct SimParams {
     pub ach_speed_max_iter: u32,
     pub ach_speed_tol: si::Ratio,
     pub ach_speed_solver_gain: f64,
-    #[api(skip_get, skip_set)] // TODO: manually write out getter and setter
+    #[api(skip_get, skip_set)]
     pub trace_miss_tol: TraceMissTolerance,
 }
 
@@ -30,7 +30,7 @@ impl Default for SimParams {
     }
 }
 
-#[pyo3_api(
+#[fastsim_api(
     #[new]
     fn __new__(veh: Vehicle, cyc: Cycle, sim_params: Option<SimParams>) -> anyhow::Result<Self> {
         Ok(SimDrive{
@@ -80,7 +80,6 @@ impl SimDrive {
         }
     }
 
-    // #[timer] TODO: fix and uncomment
     pub fn walk(&mut self) -> anyhow::Result<()> {
         ensure!(self.cyc.len() >= 2, format_dbg!(self.cyc.len() < 2));
         self.save_state();
@@ -398,7 +397,7 @@ mod tests {
     #[test]
     #[cfg(feature = "resources")]
     fn test_sim_drive_conv() {
-        let _veh = mock_f2_conv_veh();
+        let _veh = mock_conv_veh();
         let _cyc = Cycle::from_resource("udds.csv", false).unwrap();
         let mut sd = SimDrive {
             veh: _veh,
@@ -413,7 +412,7 @@ mod tests {
     #[test]
     #[cfg(feature = "resources")]
     fn test_sim_drive_hev() {
-        let _veh = mock_f2_hev();
+        let _veh = mock_hev();
         let _cyc = Cycle::from_resource("udds.csv", false).unwrap();
         let mut sd = SimDrive {
             veh: _veh,
diff --git a/fastsim-core/src/utils/interp/wrapper.rs b/fastsim-core/src/utils/interp/wrapper.rs
index 680be925..245b7d41 100644
--- a/fastsim-core/src/utils/interp/wrapper.rs
+++ b/fastsim-core/src/utils/interp/wrapper.rs
@@ -12,7 +12,7 @@
 
 use super::*;
 
-#[pyo3_api(
+#[fastsim_api(
     /// Function to get x variable from enum variants
     #[getter("x")]
     pub fn x_py(&self) -> anyhow::Result<Vec<f64>> {
diff --git a/fastsim-core/src/utils/mod.rs b/fastsim-core/src/utils/mod.rs
index f260a679..98e1403b 100644
--- a/fastsim-core/src/utils/mod.rs
+++ b/fastsim-core/src/utils/mod.rs
@@ -159,12 +159,10 @@ pub fn interp1d(
     let y_first = y_data
         .first()
         .with_context(|| anyhow!("Unable to extract first element"))?;
-    // TODO: do this once on init
     if y_data.iter().all(|y| y == y_first) {
         // return first if all data is equal to first
         Ok(*y_first)
     } else {
-        // TODO: when `Interpolator` struct is implemented, make sure this sort of check happens on init
         let size = x_data.len();
 
         let mut i = 0;
@@ -303,20 +301,20 @@ make_uom_cmp_fn!(almost_lt);
 make_uom_cmp_fn!(almost_ge);
 make_uom_cmp_fn!(almost_le);
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Default, Serialize, Deserialize, Clone, PartialEq, Eq)]
 pub struct Pyo3VecBoolWrapper(pub Vec<bool>);
 impl SerdeAPI for Pyo3VecBoolWrapper {}
 impl Init for Pyo3VecBoolWrapper {}
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Default, Serialize, Deserialize, Clone, PartialEq)]
 pub struct Pyo3VecWrapper(pub Vec<f64>);
 impl SerdeAPI for Pyo3VecWrapper {}
 impl Init for Pyo3VecWrapper {}
 
 #[allow(non_snake_case)]
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Default, Serialize, Deserialize, Clone, PartialEq)]
 pub struct Pyo3Vec2Wrapper(pub Vec<Vec<f64>>);
 impl From<Vec<Vec<f64>>> for Pyo3Vec2Wrapper {
@@ -327,7 +325,7 @@ impl From<Vec<Vec<f64>>> for Pyo3Vec2Wrapper {
 impl SerdeAPI for Pyo3Vec2Wrapper {}
 impl Init for Pyo3Vec2Wrapper {}
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(Default, Serialize, Deserialize, Clone, PartialEq)]
 pub struct Pyo3Vec3Wrapper(pub Vec<Vec<Vec<f64>>>);
 impl From<Vec<Vec<Vec<f64>>>> for Pyo3Vec3Wrapper {
@@ -566,12 +564,6 @@ mod tests {
         );
     }
 
-    // TODO: turn this back on and fix the problem it catches
-    // #[test]
-    // fn test_interp1d_with_duplicate_x_data() {
-    //     assert!(interp1d(&0.5, &[0.0, 0.0], &[0.0, 1.0], Extrapolate::Yes).is_err());
-    // }
-
     #[test]
     fn test_linspace() {
         assert_eq!(Vec::linspace(0.0, 1.0, 3), vec![0.0, 0.5, 1.0]);
diff --git a/fastsim-core/src/vehicle/chassis.rs b/fastsim-core/src/vehicle/chassis.rs
index b36aaf92..6f973d3e 100644
--- a/fastsim-core/src/vehicle/chassis.rs
+++ b/fastsim-core/src/vehicle/chassis.rs
@@ -16,7 +16,7 @@ pub enum DriveTypes {
 impl SerdeAPI for DriveTypes {}
 impl Init for DriveTypes {}
 
-#[pyo3_api]
+#[fastsim_api]
 #[derive(PartialEq, Clone, Debug, Serialize, Deserialize, HistoryMethods)]
 /// Struct for simulating vehicle
 pub struct Chassis {
diff --git a/fastsim-core/src/vehicle/powertrain/electric_machine.rs b/fastsim-core/src/vehicle/powertrain/electric_machine.rs
index ec8691bc..4b4d6b6c 100644
--- a/fastsim-core/src/vehicle/powertrain/electric_machine.rs
+++ b/fastsim-core/src/vehicle/powertrain/electric_machine.rs
@@ -7,7 +7,7 @@ use super::*;
 use crate::pyo3::*;
 use crate::utils::abs_checked_x_val;
 
-#[pyo3_api(
+#[fastsim_api(
     // #[new]
     // fn __new__(
     //     pwr_out_frac_interp: Vec<f64>,
@@ -367,7 +367,7 @@ impl Mass for ElectricMachine {
 #[derive(
     Clone, Copy, Debug, Default, Deserialize, Serialize, PartialEq, HistoryVec, SetCumulative,
 )]
-#[pyo3_api]
+#[fastsim_api]
 pub struct ElectricMachineState {
     /// time step index
     pub i: usize,
diff --git a/fastsim-core/src/vehicle/powertrain/fuel_converter.rs b/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
index c77b8018..6bd4cfb7 100644
--- a/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
+++ b/fastsim-core/src/vehicle/powertrain/fuel_converter.rs
@@ -2,7 +2,7 @@ use super::*;
 
 // TODO: think about how to incorporate life modeling for Fuel Cells and other tech
 
-#[pyo3_api(
+#[fastsim_api(
     // // optional, custom, struct-specific pymethods
     // #[getter("eff_max")]
     // fn get_eff_max_py(&self) -> f64 {
@@ -289,7 +289,7 @@ impl FuelConverter {
 #[derive(
     Clone, Copy, Debug, Default, Deserialize, Serialize, PartialEq, HistoryVec, SetCumulative,
 )]
-#[pyo3_api]
+#[fastsim_api]
 pub struct FuelConverterState {
     /// time step index
     pub i: usize,
diff --git a/fastsim-core/src/vehicle/powertrain/fuel_storage.rs b/fastsim-core/src/vehicle/powertrain/fuel_storage.rs
index bc20286d..718bf654 100644
--- a/fastsim-core/src/vehicle/powertrain/fuel_storage.rs
+++ b/fastsim-core/src/vehicle/powertrain/fuel_storage.rs
@@ -1,6 +1,6 @@
 use super::*;
 
-#[pyo3_api(
+#[fastsim_api(
     // TODO: decide on way to deal with `side_effect` coming after optional arg and uncomment
     // #[setter("__mass_kg")]
     // fn set_mass_py(&mut self, mass_kg: Option<f64>) -> anyhow::Result<()> {
diff --git a/fastsim-core/src/vehicle/powertrain/reversible_energy_storage.rs b/fastsim-core/src/vehicle/powertrain/reversible_energy_storage.rs
index b875066b..5cd0314c 100644
--- a/fastsim-core/src/vehicle/powertrain/reversible_energy_storage.rs
+++ b/fastsim-core/src/vehicle/powertrain/reversible_energy_storage.rs
@@ -6,7 +6,7 @@ use crate::pyo3::*;
 
 const TOL: f64 = 1e-3;
 
-#[pyo3_api(
+#[fastsim_api(
    #[allow(clippy::too_many_arguments)]
     #[new]
     fn __new__(
@@ -609,7 +609,7 @@ pub enum SpecificEnergySideEffect {
 }
 
 #[derive(Clone, Copy, Debug, Deserialize, Serialize, PartialEq, HistoryVec, SetCumulative)]
-#[pyo3_api]
+#[fastsim_api]
 // component limits
 /// ReversibleEnergyStorage state variables
 pub struct ReversibleEnergyStorageState {
diff --git a/fastsim-core/src/vehicle/vehicle_model.rs b/fastsim-core/src/vehicle/vehicle_model.rs
index c51ce783..3eed35a9 100644
--- a/fastsim-core/src/vehicle/vehicle_model.rs
+++ b/fastsim-core/src/vehicle/vehicle_model.rs
@@ -16,7 +16,7 @@ pub enum AuxSource {
 impl SerdeAPI for AuxSource {}
 impl Init for AuxSource {}
 
-#[pyo3_api(
+#[fastsim_api(
     #[staticmethod]
     fn try_from_fastsim2(veh: fastsim_2::vehicle::RustVehicle) -> PyResult<Vehicle> {
         Ok(Self::try_from(veh.clone())?)
@@ -826,7 +826,7 @@ impl Vehicle {
 
 /// Vehicle state for current time step
 #[derive(Clone, Copy, Debug, Deserialize, Serialize, PartialEq, HistoryVec, SetCumulative)]
-#[pyo3_api]
+#[fastsim_api]
 pub struct VehicleState {
     /// time step index
     pub i: usize,
@@ -924,8 +924,12 @@ impl Default for VehicleState {
 pub(crate) mod tests {
     use super::*;
 
+    fn vehicles_dir() -> PathBuf {
+        PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("resources/vehicles")
+    }
+
     #[cfg(feature = "yaml")]
-    pub(crate) fn mock_f2_conv_veh() -> Vehicle {
+    pub(crate) fn mock_conv_veh() -> Vehicle {
         let file_contents = include_str!("fastsim-2_2012_Ford_Fusion.yaml");
         use fastsim_2::traits::SerdeAPI;
         let veh = {
@@ -934,21 +938,14 @@ pub(crate) mod tests {
             veh.unwrap()
         };
 
+        veh.to_file(vehicles_dir().join("2012_Ford_Fusion.yaml"))
+            .unwrap();
         assert!(veh.pt_type.is_conventional_vehicle());
-
-        // TODO: come up with a fancier solution
-        // uncomment this if the fastsim-3 version needs to be rewritten
-        // veh.to_file(
-        //     project_root::get_project_root()
-        //         .unwrap()
-        //         .join("tests/assets/2012_Ford_Fusion.yaml"),
-        // )
-        // .unwrap();
         veh
     }
 
     #[cfg(feature = "yaml")]
-    pub(crate) fn mock_f2_hev() -> Vehicle {
+    pub(crate) fn mock_hev() -> Vehicle {
         let file_contents = include_str!("fastsim-2_2016_TOYOTA_Prius_Two.yaml");
         use fastsim_2::traits::SerdeAPI;
         let veh = {
@@ -957,16 +954,9 @@ pub(crate) mod tests {
             veh.unwrap()
         };
 
+        veh.to_file(vehicles_dir().join("2016_TOYOTA_Prius_Two.yaml"))
+            .unwrap();
         assert!(veh.pt_type.is_hybrid_electric_vehicle());
-
-        // TODO: come up with a fancier solution
-        // uncomment this if the fastsim-3 version needs to be rewritten
-        // veh.to_file(
-        //     project_root::get_project_root()
-        //         .unwrap()
-        //         .join("tests/assets/2016_TOYOTA_Prius_Two.yaml"),
-        // )
-        // .unwrap();
         veh
     }
 
@@ -974,7 +964,7 @@ pub(crate) mod tests {
     #[test]
     #[cfg(feature = "yaml")]
     pub(crate) fn test_conv_veh_init() {
-        let veh = mock_f2_conv_veh();
+        let veh = mock_conv_veh();
         let mut veh1 = veh.clone();
         assert!(veh == veh1);
         veh1.init().unwrap();
@@ -984,7 +974,7 @@ pub(crate) mod tests {
     #[test]
     #[cfg(all(feature = "csv", feature = "resources"))]
     fn test_to_fastsim2_conv() {
-        let veh = mock_f2_conv_veh();
+        let veh = mock_conv_veh();
         let cyc = crate::drive_cycle::Cycle::from_resource("udds.csv", false).unwrap();
         let sd = crate::simdrive::SimDrive {
             veh,
@@ -998,7 +988,7 @@ pub(crate) mod tests {
     #[test]
     #[cfg(all(feature = "csv", feature = "resources"))]
     fn test_to_fastsim2_hev() {
-        let veh = mock_f2_hev();
+        let veh = mock_hev();
         let cyc = crate::drive_cycle::Cycle::from_resource("udds.csv", false).unwrap();
         let sd = crate::simdrive::SimDrive {
             veh,
@@ -1008,19 +998,4 @@ pub(crate) mod tests {
         let mut sd2 = sd.to_fastsim2().unwrap();
         sd2.sim_drive(None, None).unwrap();
     }
-
-    #[test]
-    #[cfg(feature = "yaml")]
-    fn test_hev_deserialize() {
-        let veh = mock_f2_hev();
-
-        let veh_from_file = Vehicle::from_file(
-            project_root::get_project_root()
-                .unwrap()
-                .join("tests/assets/2016_TOYOTA_Prius_Two.yaml"),
-            false,
-        )
-        .unwrap();
-        assert!(veh == veh_from_file);
-    }
 }
diff --git a/python/fastsim/demos/demo_conv.py b/python/fastsim/demos/demo_conv.py
index e05b3c61..34c1ba23 100644
--- a/python/fastsim/demos/demo_conv.py
+++ b/python/fastsim/demos/demo_conv.py
@@ -27,9 +27,7 @@
 # %%
 
 # load 2012 Ford Fusion from file
-veh = fsim.Vehicle.from_file(
-    str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
-)
+veh = fsim.Vehicle.from_resource("2012_Ford_Fusion.yaml")
 veh_no_save = veh.copy()
 fsim.set_param_from_path(veh_no_save, "save_interval", None)
 
@@ -361,8 +359,8 @@ def get_uni_cycler():
 #     5   61.562 MiB   61.562 MiB           1   @profile(precision=3)
 #     6                                         def build_and_run_sim_drive():
 #     7   62.125 MiB    0.562 MiB           2       veh = fsim.Vehicle.from_file(
-#     8                                                 # TODO: figure out why `str` is needed here
-#     9   61.562 MiB    0.000 MiB           1           str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
+#     8                                                 
+#     9   61.562 MiB    0.000 MiB           1           fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml"
 #     10                                             )
 #     11   62.125 MiB    0.000 MiB           1       veh.save_interval = 1
 #     12   62.312 MiB    0.188 MiB           1       cyc = fsim.Cycle.from_resource("cycles/udds.csv")
@@ -379,8 +377,8 @@ def get_uni_cycler():
 #      5   61.203 MiB   61.203 MiB           1   @profile(precision=3)
 #      6                                         def build_and_run_sim_drive():
 #      7   61.766 MiB    0.562 MiB           2       veh = fsim.Vehicle.from_file(
-#      8                                                 # TODO: figure out why `str` is needed here
-#      9   61.203 MiB    0.000 MiB           1           str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
+#      8                                                 
+#      9   61.203 MiB    0.000 MiB           1           fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml"
 #     10                                             )
 #     11   61.766 MiB    0.000 MiB           1       veh.save_interval = None
 #     12   61.938 MiB    0.172 MiB           1       cyc = fsim.Cycle.from_resource("cycles/udds.csv")
diff --git a/python/fastsim/demos/demo_hev.py b/python/fastsim/demos/demo_hev.py
index aa2e5c42..29a3d8ba 100644
--- a/python/fastsim/demos/demo_hev.py
+++ b/python/fastsim/demos/demo_hev.py
@@ -27,9 +27,8 @@
 # %%
 
 # load 2016 Toyota Prius Two from file
-veh = fsim.Vehicle.from_file(
-    str(fsim.package_root() / "../../tests/assets/2016_TOYOTA_Prius_Two.yaml")
-)
+veh = fsim.Vehicle.from_resource("2016_TOYOTA_Prius_Two.yaml")
+
 veh_no_save = veh.copy()
 fsim.set_param_from_path(veh_no_save, "save_interval", None)
 
diff --git a/python/fastsim/demos/demo_variable_paths.py b/python/fastsim/demos/demo_variable_paths.py
index 7b87f917..bba00e18 100644
--- a/python/fastsim/demos/demo_variable_paths.py
+++ b/python/fastsim/demos/demo_variable_paths.py
@@ -7,9 +7,7 @@
 import polars as pl
 
 # load 2012 Ford Fusion from file
-veh = fsim.Vehicle.from_file(
-    str(fsim.package_root() / "../../tests/assets/2016_TOYOTA_Prius_Two.yaml")
-)
+veh = fsim.Vehicle.from_resource("2016_TOYOTA_Prius_Two.yaml")
 
 # Set `save_interval` at vehicle level -- cascades to all sub-components with time-varying states
 fsim.set_param_from_path(veh, "save_interval", 1)
@@ -28,7 +26,6 @@
 # directory for reference files for checking sim results against expected results
 ref_dir = fsim.resources_root() / "demos/demo_variable_paths/"
 
-
 # print out all subpaths for variables in SimDrive
 print("List of variable paths for SimDrive:" + "\n".join(sd.variable_path_list()))
 if ENABLE_REF_OVERRIDE:
diff --git a/python/fastsim/resources/demos/demo_variable_paths/variable_path_list_expected.txt b/python/fastsim/resources/demos/demo_variable_paths/variable_path_list_expected.txt
index c9ee97a7..d83991ec 100644
--- a/python/fastsim/resources/demos/demo_variable_paths/variable_path_list_expected.txt
+++ b/python/fastsim/resources/demos/demo_variable_paths/variable_path_list_expected.txt
@@ -21,8 +21,8 @@
 ['veh']['pt_type']['HybridElectricVehicle']['res']['state']['max_soc']
 ['veh']['pt_type']['HybridElectricVehicle']['res']['state']['min_soc']
 ['veh']['pt_type']['HybridElectricVehicle']['res']['state']['temperature_celsius']
-['veh']['pt_type']['HybridElectricVehicle']['res']['mass']
-['veh']['pt_type']['HybridElectricVehicle']['res']['specific_energy']
+['veh']['pt_type']['HybridElectricVehicle']['res']['mass_kilograms']
+['veh']['pt_type']['HybridElectricVehicle']['res']['specific_energy_joules_per_kilogram']
 ['veh']['pt_type']['HybridElectricVehicle']['res']['pwr_out_max_watts']
 ['veh']['pt_type']['HybridElectricVehicle']['res']['energy_capacity_joules']
 ['veh']['pt_type']['HybridElectricVehicle']['res']['min_soc']
@@ -67,8 +67,8 @@
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['pwr_loss']
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['energy_loss']
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['state']['fc_on']
-['veh']['pt_type']['HybridElectricVehicle']['fc']['mass']
-['veh']['pt_type']['HybridElectricVehicle']['fc']['specific_pwr']
+['veh']['pt_type']['HybridElectricVehicle']['fc']['mass_kilograms']
+['veh']['pt_type']['HybridElectricVehicle']['fc']['specific_pwr_watts_per_kilogram']
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['pwr_out_max_watts']
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['pwr_out_max_init_watts']
 ['veh']['pt_type']['HybridElectricVehicle']['fc']['pwr_ramp_lag_seconds']
@@ -108,8 +108,8 @@
 ['veh']['pt_type']['HybridElectricVehicle']['em']['pwr_out_frac_interp']
 ['veh']['pt_type']['HybridElectricVehicle']['em']['eff_interp']
 ['veh']['pt_type']['HybridElectricVehicle']['em']['pwr_out_max_watts']
-['veh']['pt_type']['HybridElectricVehicle']['em']['specific_pwr']
-['veh']['pt_type']['HybridElectricVehicle']['em']['mass']
+['veh']['pt_type']['HybridElectricVehicle']['em']['specific_pwr_watts_per_kilogram']
+['veh']['pt_type']['HybridElectricVehicle']['em']['mass_kilograms']
 ['veh']['pt_type']['HybridElectricVehicle']['em']['save_interval']
 ['veh']['pt_type']['HybridElectricVehicle']['em']['history']['i']
 ['veh']['pt_type']['HybridElectricVehicle']['em']['history']['eff']
@@ -134,12 +134,12 @@
 ['veh']['chassis']['wheel_rr_coef']
 ['veh']['chassis']['wheel_inertia_kilogram_square_meters']
 ['veh']['chassis']['num_wheels']
-['veh']['chassis']['wheel_radius']
+['veh']['chassis']['wheel_radius_meters']
 ['veh']['chassis']['cg_height_meters']
 ['veh']['chassis']['wheel_fric_coef']
 ['veh']['chassis']['drive_axle_weight_frac']
 ['veh']['chassis']['wheel_base_meters']
-['veh']['mass']
+['veh']['mass_kilograms']
 ['veh']['pwr_aux_watts']
 ['veh']['trans_eff']
 ['veh']['save_interval']
@@ -193,7 +193,7 @@
 ['veh']['history']['dist']
 ['veh']['history']['grade_curr']
 ['veh']['history']['air_density']
-['cyc']['init_elev']
+['cyc']['init_elev_meters']
 ['cyc']['time_seconds']
 ['cyc']['speed_meters_per_second']
 ['cyc']['dist_meters']
diff --git a/python/fastsim/tests/test_speedup.py b/python/fastsim/tests/test_speedup.py
index b1356ce9..3ab9eefd 100644
--- a/python/fastsim/tests/test_speedup.py
+++ b/python/fastsim/tests/test_speedup.py
@@ -7,9 +7,7 @@ def test_hev_speedup():
     min_allowed_speed_ratio = 8.
     
     # load 2016 Toyota Prius Two from file
-    veh = fsim.Vehicle.from_file(
-        str(fsim.package_root() / "../../tests/assets/2016_TOYOTA_Prius_Two.yaml")
-    )
+    veh = fsim.Vehicle.from_resource("2016_TOYOTA_Prius_Two.yaml")
 
     # Set `save_interval` at vehicle level -- cascades to all sub-components with time-varying states
     fsim.set_param_from_path(veh, "save_interval", 1)
@@ -58,9 +56,7 @@ def test_conv_speedup():
     min_speed_ratio_si_1 = 2.5
     
     # load 2016 Toyota Prius Two from file
-    veh = fsim.Vehicle.from_file(
-        str(fsim.package_root() / "../../tests/assets/2012_Ford_Fusion.yaml")
-    )
+    veh = fsim.Vehicle.from_resource("2012_Ford_Fusion.yaml")
 
     # Set `save_interval` at vehicle level -- cascades to all sub-components with time-varying states
     fsim.set_param_from_path(veh, "save_interval", 1)
diff --git a/tests/assets/2012_Ford_Fusion.yaml b/tests/assets/2012_Ford_Fusion.yaml
deleted file mode 100644
index 87cd0124..00000000
--- a/tests/assets/2012_Ford_Fusion.yaml
+++ /dev/null
@@ -1,65 +0,0 @@
----
-name: 2012 Ford Fusion
-year: 2012
-pt_type:
-  ConventionalVehicle:
-    fs:
-      pwr_out_max_watts: 1000000.0
-      pwr_ramp_lag_seconds: 1.0
-      energy_capacity_joules: 2124000000.0
-    fc:
-      mass: ~
-      specific_pwr: ~
-      pwr_out_max_watts: 130500.0
-      pwr_out_max_init_watts: 21750.0
-      pwr_ramp_lag_seconds: 6.0
-      eff_interp:
-        Interp1D:
-          x:
-            - 0.0
-            - 0.005
-            - 0.015
-            - 0.04
-            - 0.06
-            - 0.1
-            - 0.14
-            - 0.2
-            - 0.4
-            - 0.6
-            - 0.8
-            - 1.0
-          f_x:
-            - 0.1
-            - 0.12
-            - 0.16
-            - 0.22
-            - 0.28
-            - 0.33
-            - 0.35
-            - 0.36
-            - 0.35
-            - 0.34
-            - 0.32
-            - 0.3
-          strategy: LeftNearest
-          extrapolate: Error
-      pwr_idle_fuel_watts: 6999.999999999999
-      save_interval: 1
-    mass: ~
-    alt_eff: 1.0
-chassis:
-  drag_coef: 0.393
-  frontal_area_square_meters: 2.12
-  wheel_rr_coef: 0.007
-  wheel_inertia_kilogram_square_meters: 0.82
-  num_wheels: 4
-  wheel_radius: 0.326
-  cg_height_meters: 0.53
-  wheel_fric_coef: 0.7
-  drive_type: FWD
-  drive_axle_weight_frac: 0.59
-  wheel_base_meters: 2.72
-mass: 1644.2724500334996
-pwr_aux_watts: 700.0
-trans_eff: 0.875
-save_interval: 1
diff --git a/tests/assets/2012_Ford_Fusion_2D_test.yaml b/tests/assets/2012_Ford_Fusion_2D_test.yaml
deleted file mode 100644
index 2e402058..00000000
--- a/tests/assets/2012_Ford_Fusion_2D_test.yaml
+++ /dev/null
@@ -1,57 +0,0 @@
----
-name: 2012 Ford Fusion
-year: 2012
-pt_type:
-  ConventionalVehicle:
-    fs:
-      pwr_out_max: 1000000.0
-      pwr_ramp_lag: 1.0
-      energy_capacity: 2124000000.0
-    fc:
-      mass: ~
-      specific_pwr: ~
-      pwr_out_max_watts: 130500.0
-      pwr_out_max_init: 21750.0
-      pwr_ramp_lag_seconds: 6.0
-      eff_interp:
-        Interp2D:
-          x:
-            - 0.05
-            - 0.1
-            - 0.15
-          y:
-            - 0.1
-            - 0.2
-            - 0.3
-          f_xy:
-            - - 0.0
-              - 1.0
-              - 2.0
-            - - 3.0
-              - 4.0
-              - 5.0
-            - - 6.0
-              - 7.0
-              - 8.0
-          strategy: Linear
-          extrapolate: Error
-      pwr_idle_fuel_watts: 6999.999999999999
-      save_interval: 1
-    mass: ~
-    alt_eff: 1.0
-chassis:
-  drag_coef: 0.393
-  frontal_area: 2.12
-  wheel_rr_coef: 0.007
-  wheel_inertia: 0.82
-  num_wheels: 4
-  wheel_radius: 0.326
-  cg_height: 0.53
-  wheel_fric_coef: 0.7
-  drive_type: FWD
-  drive_axle_weight_frac: 0.59
-  wheel_base: 2.72
-mass: 1644.2724500334996
-pwr_aux: 700.0
-trans_eff: 0.875
-save_interval: 1
diff --git a/tests/assets/2012_Ford_Fusion_3D_test.yaml b/tests/assets/2012_Ford_Fusion_3D_test.yaml
deleted file mode 100644
index cceb0f6f..00000000
--- a/tests/assets/2012_Ford_Fusion_3D_test.yaml
+++ /dev/null
@@ -1,79 +0,0 @@
----
-name: 2012 Ford Fusion
-year: 2012
-pt_type:
-  ConventionalVehicle:
-    fs:
-      pwr_out_max: 1000000.0
-      pwr_ramp_lag: 1.0
-      energy_capacity: 2124000000.0
-    fc:
-      mass: ~
-      specific_pwr: ~
-      pwr_out_max_watts: 130500.0
-      pwr_out_max_init: 21750.0
-      pwr_ramp_lag_seconds: 6.0
-      eff_interp:
-        Interp3D:
-          x:
-            - 0.05
-            - 0.1
-            - 0.15
-          y:
-            - 0.1
-            - 0.2
-            - 0.3
-          z:
-            - 0.2
-            - 0.4
-            - 0.6
-          f_xyz:
-            - - - 0.0
-                - 1.0
-                - 2.0
-              - - 3.0
-                - 4.0
-                - 5.0
-              - - 6.0
-                - 7.0
-                - 8.0
-            - - - 9.0
-                - 10.0
-                - 11.0
-              - - 12.0
-                - 13.0
-                - 14.0
-              - - 15.0
-                - 16.0
-                - 17.0
-            - - - 18.0
-                - 19.0
-                - 20.0
-              - - 21.0
-                - 22.0
-                - 23.0
-              - - 24.0
-                - 25.0
-                - 26.0
-          strategy: Linear
-          extrapolate: Error
-      pwr_idle_fuel_watts: 6999.999999999999
-      save_interval: 1
-    mass: ~
-    alt_eff: 1.0
-chassis:
-  drag_coef: 0.393
-  frontal_area: 2.12
-  wheel_rr_coef: 0.007
-  wheel_inertia: 0.82
-  num_wheels: 4
-  wheel_radius: 0.326
-  cg_height: 0.53
-  wheel_fric_coef: 0.7
-  drive_type: FWD
-  drive_axle_weight_frac: 0.59
-  wheel_base: 2.72
-mass: 1644.2724500334996
-pwr_aux: 700.0
-trans_eff: 0.875
-save_interval: 1
diff --git a/tests/assets/2012_Ford_Fusion_ND_test.yaml b/tests/assets/2012_Ford_Fusion_ND_test.yaml
deleted file mode 100644
index 5faceae5..00000000
--- a/tests/assets/2012_Ford_Fusion_ND_test.yaml
+++ /dev/null
@@ -1,83 +0,0 @@
----
-name: 2012 Ford Fusion
-year: 2012
-pt_type:
-  ConventionalVehicle:
-    fs:
-      pwr_out_max: 1000000.0
-      pwr_ramp_lag: 1.0
-      energy_capacity: 2124000000.0
-    fc:
-      mass: ~
-      specific_pwr: ~
-      pwr_out_max_watts: 130500.0
-      pwr_out_max_init: 21750.0
-      pwr_ramp_lag_seconds: 6.0
-      eff_interp:
-        InterpND:
-          grid:
-            - - 0.05
-              - 0.1
-              - 0.15
-            - - 0.1
-              - 0.2
-              - 0.3
-            - - 0.2
-              - 0.4
-              - 0.6
-          values:
-            v: 1
-            dim:
-              - 3
-              - 3
-              - 3
-            data:
-              - 0.0
-              - 1.0
-              - 2.0
-              - 3.0
-              - 4.0
-              - 5.0
-              - 6.0
-              - 7.0
-              - 8.0
-              - 9.0
-              - 10.0
-              - 11.0
-              - 12.0
-              - 13.0
-              - 14.0
-              - 15.0
-              - 16.0
-              - 17.0
-              - 18.0
-              - 19.0
-              - 20.0
-              - 21.0
-              - 22.0
-              - 23.0
-              - 24.0
-              - 25.0
-              - 26.0
-          extrapolate: Error
-          strategy: Linear
-      pwr_idle_fuel_watts: 6999.999999999999
-      save_interval: 1
-    mass: ~
-    alt_eff: 1.0
-chassis:
-  drag_coef: 0.393
-  frontal_area: 2.12
-  wheel_rr_coef: 0.007
-  wheel_inertia: 0.82
-  num_wheels: 4
-  wheel_radius: 0.326
-  cg_height: 0.53
-  wheel_fric_coef: 0.7
-  drive_type: FWD
-  drive_axle_weight_frac: 0.59
-  wheel_base: 2.72
-mass: 1644.2724500334996
-pwr_aux: 700.0
-trans_eff: 0.875
-save_interval: 1