Early model 345 electrical nightmare

I've been dealing with a 345 for some time now. I'll give you the long version so you have all the details. Customer bought this used from a JD dealer in pieces. had been hit/rolled/or on fire at some point by previous owner who was a landscaper. They bought ALL NEW sheetmetal, hood, seat, decals etc. Customer strips entire thing down to bare chassis, paints chassis and reassembles with new parts. The machine looks like new. Now on to the real problem. Was brought in because it cranks all the time when the key is turned to the on position, not even the crank position. So we replaced the key switch circuit board assembly. Same problem. At this point we knew we were in for a doozie. The wiring harness has been hacked to death by someone, butt connectors, splices, electrical tape, you name it. Traced the wiring, found a short under the motor where a wire had merely rubbed thru and was grounding out on the frame. fixed it, another new keyswitch/board assembly, also replaced the timing delay module at the same time. fixed, started and ran as it should for two days. then back to same issue. Ughhhh. Obviously it really needs a new wiring harness, once that is replaced, what modules should I start with again? Find it hard to believe no one repairs the old keyswitch boards and just solders a new relay in Thanks for the help guys!