Thanks Glen for the advice. It was very helpful, I need to prepare everything before doing it. Now I need more help from any one out there.
I just bought a used rear differential for my 89 800E and I don't know how good the seals are so I'd like to replace these seals before putting this real differential into the car, but I don't know how to go about taking the old seals out. Do I need any special tools for this or perhaps I don't even need to replace these seals at all. Please give me some advices on this. Thanks in advance for your idea and time.