It's located on the side of the transmission. Follow your gear shift lever to the shifting rod to the NSS - looks like this - http://catalog.peachparts.com/RenderScriptTemplate.epc?_cmd=epccat_VehicleAAA&cookieID=2EV00YCOB2FB1B802X&yearid=1994%40%401994&makeid=MB%40%40MB%40%40X&modelid=E%2D420%2D001%40%40E+420+Sedan&catid=J%40%40Transmission&mode=PA&subcatid=J4050@@Neutral+Safety+Switch&source=www.peachparts.com&clientid=catalog.mercedesshop