126 door panel, piece of cake.
Unscrew the lock knob. On the outer trailing edge of the window surround is a very small phillips head screw, remove it and lift up on the inner trim piece. You also have to remove the two phillips screws that retain the striker trim piece, a chrome u-shaped piece at the door latch. Gently pry out the black plastic insert behind the inside door latch handle and remove the phillips head screw. That will allow you to move/remove the leading piece of trim, which will gain you access to a large phillips head screw that retains the upper portion of the arm rest.
Next remove the two phillips head screws that are accessed from the botton of the arm rest. Arm rest should now come off. There is also a small phillips head screw or two at the lower edge of the panel that need to be removed. Now you should be able to simply push straight up on the panel and it should come loose. Do not try prying ourward on the panel as there are "cam" levers that pull the panel tight to the door when it is pressed down into place.
There will be a couple electrical connections for the courtesy light, the seat adjustment switch is attached to the steel of the door and will not come out with the panel. The only other thing you should have to remove to access the regulator/sliding jaw is the moisture barrier. Be sure to use care when removing the barrier and reinstall on assembly.
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.