Switch fits in the center wooden console box between the seats, directly behind the ashtray. This switch is mounted on a metal "Z" shape piece covered in either matching leather or MB-Tex (depending on what interior you have) that has three screw holes for screwing to the wood box bottom. This mounting piece fits directly behind the ashtray with the switch the same knob as your lighter but with a green plastic insert. This switch also operated a rear red foglight (only on Euro models). Note some SLs came with ywo switches mounted there, for foglights and for the heated rear window of the hardtop.
Bob