Hey MacGyver-
Good news! The autodimming mirror will work in your car.
Check out 2phasts site for installation instructions:
http://www.2phast.com/500e/
His car is a 500e but the mounting bracket should be the same for your car. I have also done this installation in my 94 E320. I picked up an autodimming mirror out of a CLK (w208) for ~$35 shipped. The only thing you need to do is hook up power and ground to the mirror. As an added bonus the homelink programmable garage door openers also work.
Good luck!