Orange Pi 5 k3s cluster?

I’m currently trying to piece together the smallest cluster I can inside of a pc. The main computer is a 7950x gaming computer basically, but my hope is to run proxmox on the main rig, and have 8 orange pi 5s in the bottom, all networked together, and also to the pc. My questions mainly pertain to how I can get them to all talk to eachother the fastest. It has an e key m.2, and a m key one, and 2 2.5gb lan ports, 2 type c, all of which seems like an avenue to take, but I’m struggling to find the best method to get them going with kubernetes and proxmox specifically. If anyone has suggestions for any interface that could even talk over pcie directly. That I could imagine would be the fastest, or at least has less overhead probably, but I’m also not super experienced with arm sbcs in general.

I was doing some research, and type c seems like the best idea, the fastest I can get with nvme is 10gbps over ethernet, and each adapter costs more than the pi itself. Sonnet makes an 8 port type c card, which should allow this sort of crap. I’m not sure if it’s necessary/a good idea to also use type c to network each pi to eachother, in which case, I still need some adapters, but at $30-$40, that seems more reasonable.

Mikrotik recently came out with an 8-port 2.5G & 2x 10G SFP+ switch, probably the cheapest and simplest option.

be warned, the the “m.2” slots are not full speed. iirc they are pcie gen2 x 1