X2, Craigslist is full of scammers. All Camaro's and Firebirds/ TA's from 82-02 used either 7.5 (early third gens) and 7.625 (later third gens and fourth gen's) also some 3rd gen's were equipped with a Borg Warner 9 bolt which was a 7.75 ring gear. If your looking for a used 8.5 carrier you can check the salvage yards for 80's caprice's or impala's. I know some of these were equipped with 8.5 rears, but be sure to check the spline count of the axles to make sure it's the same.