the rears never locked up. and I was going to switch to disc in the back too. got the kit, but waiting on a sure grip before I rip the rear apart for the kit.
so I figured I could wait and see if I needed it after that. plus I have one from a 68 sitting in the garage, but the mix of chevy master cylinder and such seemed to screw me up, so I would need new lines. it just kept snowballing, so I never got around to it.