I looked at the diagram in the Eaglepedia and I happend to think of a couple of things. First, which headlights did you remove that made the other two work okay, the high beam or low beam? If you took out the high beam, it is possible that something is wrong with the diode pack that goes from the switch. If the diode is shorted or "burning out" then it could cause the circuit to try and trip between high and low beam which will eventually burn out the switch. Second, only the high beam are connected to this diode pack as it appears on the diagram so if the low beams work without the high beams plugged in, that may be your culprit. Otherwise, a bad ground connection or corrosion on the terminals.
It appears that the green wire on the diagram is the high beam select line to activate the high beams and/or fog lamps.