Is 6.2 and 6.5 flywheels interchangeable? Show different part numbers. Also is gr starter different from Auto to man trans? What I'm doing is taking motor out cucv and putting in a k20 sm465 4x4. The k20 6.2 broke crank at 300k plus. I have serval of these trucks why is some louder than others at idle? Thanks again for the advice