The plastic seat-shaped piece just pull straight off. Then you have to undo the plastic cover behind the door handle, remove that, remove the small screw that holds the door handle fascia on, then remove the seat switch plastic cover by putting a thin flat screwdriver in at the front center of the switch to unlock a tab, then pull out and forward on the switch cover. Then remove the door trim piece that's next to the glass (two screws from outside edge of door)...then remove the door strike plate on the door (two screws...the chrome "C" shaped piece) Then remove the three big screws that hold on the door handle, one at the top by the door release handle, one in the center, and one recessed up inside the handle. Then the door panel lifts up and out/off the door. Be sure to unplug the door light wires (or remove and unplug the light ahead of time)

Install is reverse of removal. Be gentle as the plastic hooks like the break off.

I've gotten so fast that I can remove and reinstall a W126 door panel in about 4-5 mins.

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