just a thought but how were the mounts when you took everything out?

 

Since the vibration started I have replaced the motor mounts, transmission mounts, u-joints, re-balanced my wheels, put different wheels on, and replaced one of my rear axles (i slid into a curb a few years back so i thought it might have been a little warped and maybe became unbalanced when the transmission was dropped for the new flywheel, clutch etc..)

 

is the weight built into the flywheel like the oem?? if not and it has a spot to bolt one on, = time to remove flywheel and bolt the proper one on.