Yes gm c10 on 73 went rubber bushings in a arms
http://67-72chevytrucks.com/vboard/s...d.php?t=456889
I had seen a ball joint size charts from cpp
63 to 70 71 to 72 73 to 87
Ball joints are fully interchangeable in the a arms
Spindles are year related as the tampered holes are a different sizes