I have a 60A 5 Speed with it's own fork and carrier.
It's fitted to my A12 which has a lightened flywheel and brass button clutch. No dramas whatsoever, I did have an issue at one point (similar to yours) but I just changed the adjustment.
Did you use the shorter or longer carrier? It's sounds like the thrust bearing isn't even touching the pressure plate fingers so something is too short or the fork needs some alteration. But honestly I thought the adjustment would solve the issue.