First, welcome to the MOC!!!
A lot could have happened in the last 15 years to affect the wiring. AFAIK, there was no standard wiring diagram for the 12V system in the old days (or never for the 120V side).
Look at Post #3 in this Thread for a detailed drawing of how the wires are supposed to run. Just remember the colors may not match up with your year wiring.
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