I would shoot for .125(1/8 inch) clearance and or max end play between the input shaft and the crankshaft when sitting still with every thing tighten up as it will be run including the drive shaft You don't want the input shaft ever touching the back of the crankshaft hole, never
Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
You don't want the input shaft ever touching the back of the crankshaft hole, never 
