I am going to try to give back some. I am only a junior member but I can tell you what I did on my 190. Hope it's the same. On the bottom of the back of the seat there are two screws. Take them out and remove the back of the seat. Inside you will find the nut that holds the armrest on. Remove that and your armrest is out.
1988 190E 2.3 (178,000)
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