My 1973 scamp is almost ready to go, or so I thought. I have a completely rebuilt 512 RB, 727 trans, 8 3/4 shortened rear. SS springs. Competition engineerings drag shocks.. During hard acceleration there is not much vibration but cruising at 3500 rpm, 72 mph there is tremendous vibration coming from the driveline. My measurements are relative to gravity on a lift. The transmission output shaft is pointed down 1-2 degrees. The pinion is pointed down 7 degrees as well. I understand that the rear end pivots up during hard acceleration and that may be why I do not get the vibration. View attachment 1715533907 Is the only way to make this better to redo the perches? Can shims help this?