I have remote door lock/unlock of my 1986 300sdl, my son's 1992 400e, and my "spare" 1988 300e. Autopage makes it. In fact, on the 300sdl I just have remote door, on the 300e i have remote door/remote start, and the 400e has all the above with alarm. Auto stereo dealer installed all the systems, with the remote open costing $119, the remote open/start costing $179, and the 400e is a full blown send/recieve unit that was about $379. Works perfectly and I would never ever do without!