What Jerry is saying is when you bolt the pressure plate to the flywheel, and it compresses the clutch fingers, it may be different on the two different clutches. I understand that would involve bolting both clutches to the flywheel under the truck or removing the flywheel to get that measurement. However, if both clutch stack height (clutch pressure, plate and throwout bearing) match (where the clutch fork makes contact), that would tell you if the new clutch is the problem.
Did you measure your throwout bearing?
