I just bought a RMS set to do a coil-over suspension. Bill changed the angle where the arms come into the BJ cup. The older style had a large loop, the newer look more like the Magnum Force ones.
I'm guessing here; but I believe the change was driven by tire/arm interference on large/wide front tires that required some shimming to correct. I think the new design cures this issue. RMS could answer for sure.
