i have a 1980 sand piper motor home by execetive and when i bought it the generator had been takin out but the starter switch in the house is still there along with the wiring. so i purchased a onan 6.5 generator from a local wrecking yard and the wiring for the switches  is the same but the question i have is from the generator to inside the house is a little different. there are only 2 wires coming off the generator the go in to the electrical box inside the generator compartment that run inside but there are 3 wires inside the electric box. is there anyone out there that might know what the 3rd wire might be for or have a website that will give me a diagram to wire it up correctly. the generator model # is 6.5 nh-3cr-12014d and the serial # is f763176743 thanks in advance for any input and help