Ok I have a 91 RS and was wondering what to look for when buying a posi unit.....like what diameter? 7.5, 7.6, 8.5?

What diameter are these 10 bolt rear ends? And what are the probable ratios that I could use?

What kind of carrier is good? I'd like some 3.23's or somewhere in that area? I am looking for one on ebay right now and I am not sure what will bolt in for this car. Thanks!

 

7.5 and 7.62 are same thing, just GMs way of messing with your head. the carrier has no ratio, you can bolt up any gear set to it you want to get the ratio you want.