If he's talking about the 'triangle' (dash vent) near the headlight switch in this photo:
Then he is probably going to send an incorrect switch again. The ti and E36 z-series cars have a pull-type headlight switch, with the dimmer rheostat built into the switch. All other E36's have a switch like the one pictured above with the dimmer not part of the switch. I can understand someone at a wrecking yard not knowing the nuances between certain models for every single make of vehicle out there, but one would think that somebody who deals exclusively in BMW parts all day, every day would not only know these differences, but could probably recite specific part numbers off of the top of their head.
Let me know if you end up needing the switch- I'll dig around in my storage locker, but I'm pretty sure I have one. Good luck!