I have an early style heater box that has 4 wires connected to it in a cross type pattern. One of those is the earth which has a female type connector. The problem is the other 3 wires. All of the books I have seen don't jive with what color wires I have. The colors are green/white, red/green, and green yellow. Any help in identifying where these thing s go is greatly appreciated. The pattern is something like this: | | | ---ground! |