Hi, took out a bad heater/fan/light fixture and installing a new one. the old one was a major pain to remove and in the process, i can't remember how they had it wired. there are 3 switches but only 2 12/2 wires going to the fixture. The instructions talk about a red wire that I don't have. I have put a tester to the wires and that only accounts for 2 of the switches (heater#1 and the fan#2) am I over thinking this? How do I get the light to work too?