'65 Pontiac/Chevrolet upper ball joint, same?
 

I wonder if the '65 big Pontiacs and Chevys share the same upper ball joints?

A quick trip thru the parts books shows totally different part numbers Pontiac vs Chevy.
Pontiac numbers from 1972 parts book are:
group # 6.178
9794247 for right hand
9794248 for left hand.
Same parts used 1964-1970 for B-body cars

Unless you have a Canadian Pontiac, they are different.

Yep, went through this last summer when I rebuilt my entire suspension. Different parts. Some of the rear bushings may be the same, but I can’t recall off the top of my head.