So there was achange in 82 and up?
Was not aware of that........
So lets go with favorite gear vendor....What's your choice and why?
Just my own experience I've always used GM gears (3.42 & 3.73's) or Richmond (4.11's). As far as the change 81 and older use a different rear pinion bearing if memory serves me correct (smaller for 76-81). I've always used a Ratech master bearing kit out of a local bearing supply house and if there was an issue with the sizing they would gladly do an exchange. As far as who's gears and why... Gm or American Axle gears were the easiest to set up and ran the quietest. The Richmond set was a easy set but after about 500 miles they have a very light howl on deceleration but, they are also attached to a Detroit Locker which is not all of that quiet anyway.
Just my $.02