I put 3:42's in my olds, It had 4:11's for a while I started to get worried with the oiling system at the higher sustained engine rpm. The 3:42 work fine with the 455 a blast to drive and good all around gear. Your car is a 72 so it should have a corp 10 bolt with 28 spline axles, parts are very available at a decent price, you might just post a wanted ad, but you will need your 5 stars
