ok, I've got 3 differentials... Jaybob's original one, my pull from my parts wagon, and the diff from a 95 parts wagon.

I think the 95 is the best bet, as it's got the lowest miles...
I'm thinking I'll pull the yoke, change the grease seal, and install the yoke from my 87 parts wagon, and see if I can GUESS the preload...
I could pull the pinion, and replace the crush bushing, and set factory preload I guess... but without specs on how to do it, I'm not sure I can.

if I find the specs, I suppose I could rebuild the other two...

what say you crowd!

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!