I put all sorts of shims and ball bearings all over the car to tighten it all up.

Thank you for all the tips, and sizes, i have replaced all of my ball cups with RPM 4-40 heavy duty cups.

Took apart my diffs, and replaced the bushings with 5x8x2.5 sized bearings, and on each side i put 4 (!) 5mm 0.2mm thick shims to remove the slop from the drive cup, and from Marv's tip, there's a spring pushing on the dogbone.