Starting at the bottom of this photo. I first removed the black plastic dress cover at the door release. You pry this out carefully at the right side where you see two small slots. A small slotted screwsdriver works well here. Then remove the two electric seat motor buttons seen above.

Above is a picture of the window motor and regulator assembly on a 1984 Mercedes 300SD. It is held in place with 6 fasteners. Three nuts on the motor assembly section and three bolts on the regulator arms.