I've done a little research and called a few shops. I need to know if you can put a 3 series ring and pinion in a 2 series case by adding shims. One person that I talked to said he would have to order whole new diff. case to fit my desired 3.23 or 3.42 ring and pinion in the stock 2.41 case. It's a GM 10 bolt, 7.5. Thanks for your help.

 

George, if you don't get an answer over here after a while, try Realoldspower.com. There are a lot of very knowledgeable guys over there that visit the site every day. If you post the question there you will get an answer. I can't help you other than that.