Thrust bearing end play
 

I'm installing a rebuilt engine, and the rebuilder recommends at least .006 inch thrust end play after the trans is bolted to engine. There doesn't seem to be any end play, or at least less than .002. Unfortunately, I did not measure the end play before I bolted the trans to the engine. What could cause the zero to no end play when bolting up a manual 6 speed trans? I drove the pilot bushing in flush with the face of the crankshaft. Is it possible for the trans drive shaft to press against the pilot bushing and cause zero end play? What else could cause this problem.
Thanks,
Jeff