Mark,
What part are you having trouble with? I just pulled off all 4 door panels on my '83 300SD prior to repainting and can offer some help. Maybe someone else here can give you a quick rundown of the steps (I don't remember from memory!) but I will mention to "lift" the door panel from the door, not pull it away like you do on most other cars. The door panels on these cars have hooks rather than plastic pin-type fasteners. Don't want to break those hooks! Ask me how I know :<
Neal
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Neal Bhatt -
bhatt@ic.net
'83 300SD 190k