Even that door is beautiful.
Did you look in the DIY section above for clues? The W124 door "check strap replacement" article tells how to remove the door panel for that car. There may be some similarity. The W124 door handle is pretty much bolted to the door. I expect your coupe's handle is well attached also.
When you pull the W124 panel, you have to take off the little knobs for the seat controls. I noticed they are still in place in your photo.