I think JP has it right.
Wiring nightmare at the moment but if you're gonna wake the bike up - ! - the easiest way will probably be choose a simplified chopper-type wiring diagram from Tech and just replace all the wiring. If you've done vehicle wiring before, simple. If not, great opportunity to learn because there's not an awful lot needed to get that bike fully electrified. Grab some coloured tracer wires, connections, wire cutters and a crimping tool. Photos, questions, there's lot's of people here that will help get 'er sorted. Cheers, Raymond