I am planning on taking out my rear axle this winter and swapping it out back to the original 3.31 12 bolt Posi, instead of the 4.11 gears that are in there and then cleaning it up, repainting etc.. On the pinion flange for a 68, were they originally the Ubolt set up or the strap set up? Mine currently is the Ubolt, but I have seen different articles and replacements that also are the strap setup. I didn't find any strings discussing this particular topic. Thank you for any help. The car has the original Muncie M21 4spd, 350 CI. Thanks for any help, much appreciated.