[Steeveedee]

If I understand correctly, '68-'72 A-body cars can use the '73-'87 upper control arms for improved handling, which requires a bunch of other modifications (different ball joints, shocks, etc). Are you going to be road racing your truck? Otherwise, just leave it as it is, IMO. My truck has been pulling a trailer since it was new with the factory design, and steers just fine.