You are a freakin' GENIUS!!

[macmeister1967]

Although I still had a Qualcomm Atheros QCA6174 802.11ac Wireless card installed, I have a DW1560 on order (in transit from China, I may never see it)... I gave your setup a trial run, and it ran absolutely superbly...

I don't think there was a single issue, used Bluetooth mouse the whole time without issue... I couldn't do the 4K format, as I have a replacement NVME SSD (Samsung 970 Evo) and it only showed as 512 kb Sectors, but I formatted entire drive for macOS in Disk Utility, and that apparently takes care of the 4K alignment issues?!

I will certainly be switching back to macOS when my new WiFi/BT card appears...

Just out of interest, the Killer Wifi only seems to have one antenna port? was I looking at the correct thing? or am I in trouble with soldered-on Wifi and that was just the Bluetooth card I was looking at?

[macmeister1967]

Never mind, it looks like the WiFi card has a brace/cover over the connectors, making them hard to see... there are two antennae cables available...