Also check all the relays for function. If you have the wiring diagram, you should be able to trace out your current no power problem. As to changing the harness, since you can't get a new one, you could just be changing one set of problems for a different set. Unless there is something really wrong (mice), the wiring should be ok. What goes bad are the connectors not the actual wiring. So repairing what you have is probably the best approach.