Which M2 slot to use Hero VIII wifi

[netranger6]

I have a built Lumous, by Digital Storm. Currently 520 Firecuda 500gb as primary, and a spinner for secondary. I just purchased the Evo Pro 980 in 1 Tb. The firecuda is in the slot closest to the CPU (Ryzen 3900x). Was wondering a number of things:

1. Does it matter which slot I use? Or does the one closest to the cpu mean its faster to the cpu?

2. I was thinking of swapping the 2 out, and putting the OS from the FIRE CUDA onto the 980 Pro. Any thoughts? Should I install it the copy it all over, adjust bios for boot?

3. Should I do all of this externally, or slap the 980 in the second M2 slot, copy or clone the firecuda over. Shut down, swap stick positions, boot, reconfigure BIOS boot, and go for it?

My spinner is gonna be a bulk drive, as I am coming from a decade with a Mac. Gonna get all I need and want off of it, then nuke it.

Appreciate your responses man. Been out of the PC game a minute.

SPECS:

3900x, 32gb Vengeance RGB PRO CL16 (16/18/18/36), Geforce 2070 Super, Asus ROG Hero VIII Mb, 850 watt ps, AIO water cooled to CPU.