I had a 70 Monte that had a BOP 10 bolt they have athe scallops on both sides of the center section where the axle tubes are. Early 8.2 Chevys had a cover like a 12 bolt chevy. The later 8.2 and 8.5 chevy is very similar. The best way to be sure is to pull the cover and measure it and look for a part number on the ring gear. Try this site to see if it helps BOP link Here is a pic of a BOP 12 bolt