I have a 88 camaro 5.0 TBI, I belive it has stock 2.73 gears with and open rear end (i know the rear end is open for sure.) I found a diff on ebay from 97 trans am with 3.23 gears, 27 spline do not know if it has posi or how to tell. I'm looking to get posi of the swap but did not know if the gears would need to be swaped. Want to save money by purchasing something used. I have never done anything like this, i feel that iwould be able to do it but any information will be very appreciated. My camaro is an automatic. Do i have 28 spline axles? Is 27 spline correct for a 97 trans am?

 

A 97' should have 28-spline axles. Your 88' does not, I think it has 26-spline axles, that diff will work you car if you swap in later 28-spline axles. Not only do you need those axles, but you must use the 3.23 gears because that posi is a 3-series carrier ( won't work with gear ratio in the 2s ).