When I narrowed the 1/2 ton Ford Camper Special Dana 60 for my 55 I used Toms Diff. axle ends that use Olds Bearings and Camaro / Chevelle backing plates & drums. I have recently learned that 77 Cutlass and some full size GM cars until 96 use same axle ends with 11 inch drums instead of 9.5. I just completed the swap and when I get my new tires on my 15X10 Torq Thrust I am ready to test drive. My 15x8.5s are going to visit my 67 Camaro with a pair of 15X6. Next up ditching the Metric calipers on 55 for 77 Cutlass ones.