Call Carl at Bergwerks regardless, he might have something.
Also contact Rick at RC Imports (
http://rc-imports.com), he might have something, OR he can rebuild it inexpensively and he has the proper tools.
I run SWEPCO 80W-90 diff oil. It already has limited-slip addictive, and works find in non-limited-slip diffs. Ask Rick about it. SWEPCO has been proven (do a search) on the track.
You could also run SWEPCO 80W-140 if you do a lot of hard 1st gear runs. I get my SWEPCO from RiteGear (
http://www.ritegear.com).
:-) neil
1988 360TE AMG
1993 500E