When these cars were new, and by that I mean when these rear ends were new, techs had to be trained in how to repair them since they were like nothing else on the road.

A variety of special tools are needed to put the insides together. The manual tells how to do this and it is complicated by anyone's standards.

Mercedes finally quit repairing these and started sending them out to some shop in California for rebuilding. Today I think the Classic Center can guide you in where to send it. They may be able to rebuild it themselves. If so this might be the way to deal with the problem.

If not then replacing the entire rear end assembly is the way to go. I should think that any rear end assembly from any 108 would work so you would not lose your rear discs.

Look this over carefully as there are two leading arms that bolt to the body right under the bottom of the rear seats. Note that there are two springs in there somewhere and these tend to, when the bolts holding the arms to the body are removed, expand at a very rapid rate. Rapid enough to take a finger off if you are not ready for them to release.

These are also quite heavy so borrow all the jacks you can find to lift this into place.