[Stano]

I put 2 1/2 drop spindles in front of my 67 and 4 in. springs in the rear and I measured my rearend and it is centered to the 16th of an inch. So maybe after years of service as in anything, things move and flex to get out of alignment. My 67 has less than 100,000 original miles on it and hasn't been worked real hard in those years. Besides its been parked for extended periods of time twice. Or maybe the factory had big tolerances in frames in our trucks and some were right on and some weren't.