I want to change out the ring and pinons in my '69. I notice that SOR sells ring a pinions for 58-67, 68-72, 72-74, 74-78 etc. What are the differences in the kits? I would like to find used 3.70 ring and pinions or 3rd members to fit with my stock axles (coarse splined, right?) and driveshaft flanges. I imagine that there are a lot of gears available from 60 series cruisers who are going the other way. What should I start looking for and what should I avoid? I am willing to set up new rings and pinions; I have the time and patience and equipment to set up gears if I need to.