Thanks for providing other things to check!
Transmission was swapped out with "new" one with absolutely same results.
If bell housing was misaligned it seems like it would have shown up earlier during run in? I don't know - just asking?
Any good way to check flywheel tightness and thrust bearing through inspection plate? Ideally without removing clutch. Assuming the flywheel was torqued properly do they tend to come loose so quick?
I was hoping someone would say inspection cover clearance or starter!