I did this recently on my 1991 300CE. There are plenty of threads on this topic. The bushings are only about $1 each (only plase I found them was AutoHauzArizona), you need 2. If your car is similar to my car, it is easiest to remove the linkage and do one of the bushings on the bench. The other bushing has to be done under the car and is trickier. Both are done with a bolt/nut,washer pusher and socket receiver contraption made up from your tool chest. You are tightening the nut on the bolt and pushing the bushing on. Some have suggested first putting the bushing in hot water, while others with Popeye fingers say just reach up and squeeze them in. It is an easy straightforward job but can be time consuming if you don't have the right combination of tools.

glenmore
1991 300CE
2000 C280
1990 LS400