Body shims
Add shims there. Check all 8 mounts.
It differs from car to car, you need to check yourself by measuring, sorry!
You will have to shim yourself just like the factory did when they originally placed it. If you have had the body off and the frame straightened, original shim packages doesn't matter anyway. Most restorers wil finish the frame, and set the body and the tolerances, ie meaning door jambs, fender alignment....pull the body back off and complete the resto of the body. Doing it this way lessens the chances of chipping or damaging fresh paint.
Also, original frames from AO Smith had a very large delta in variance they were allowed to work with, meaning one corner of the frame could 1/2 inch off than the opposite corner. Today, if have a frame is straightened, you will get a much more 'finished' product than 30 yrs ago.











