My passenger side mirror began to stutter and throw "implausible signal" codes in reverse gear. Not trusting the clowns at the dealership, I ordered a new motor (Versteller 3DO 959 578C) and Tool 80-200 specified in Bentley and "went for it."
Insert tool at top after pushing mirror in at bottom. Be sure to protect the paint with duct tape. Pull back gently on inside of mirror.
Mirror open. See motor attached to housing on right.
Unscrew 3 motor mounting screws.
Unplug wiring in back.
Careful not to lose screws in housing! They are acually Pozidrive as opposed to Phillips.
Plug in new motor. Mount to housing with 3 screws. Carefully mate mirror to motor and press it into place.
Here is how the motor (unmounted) lines up with the mirror. It is held in place only by the plastic "fingers" on the mirror backing.There really is no use here for the notch in Tool 80-200.