I just replaced mine on my 1987 300E, do yourself a favor and buy a manual and parts list for your car, this will tell you exactly where to locate the unit and how to change it, mine was easy to find, plugged in the replacement one and let it hang down while I test drove and since it fixed the problem, when home and took off a few dash parts and job done, without knowing what to look for where I would still be looking for it.

__________________
Jerry

2004 SL500 Black 55K Miles
2002 s500 Black 90K Miles
1986 300E Gold 233K Miles
1966 Twin Cessna 320D
1989 Jeep Cherokee 233K Miles
1994 Ford Van E150 399K Miles