that's some good info,but i'm sure i read in an old book somewhere about a detroit locker being used in the very earliest 8.75 rears....i have a 4.10 that has a dl in it and it is a 983 or 985 housing and i think 58 ring gear.i pulled it out of an old truck...didn't look like it had been into as in no obvious signs,but it was old then too.