||Electricals are a trouble spot. no matter WHAT works today, if it's original wiring, it's breaking at the first chance. 30+ year old electricals aren't reliable. you REPLACE those wires, and you can do it all at once or in pieces, which hurts worse. but, do Not Patch It Again. when you do replace, replace everything with new, continuous, properly fused and grounded, and HEAVY ENOUGH gauge, not under spec.
electricals are a huge pain, get it over with.
did anybody mention this thing was going to eat money about 5 times more than your budget?
it will. 2000$ conversions turn into 10,000$ conversions. then you're broke and havn't any gas money. and need two more tires.
so, you were warned. have fun!