I just got a new to me 1992 u280 gv 8.3 cummins which runs and drives fine. It was last owned by a tweaker who cut off random wires through the coach and removed the entire dashboard and wiring. I need help figuring out the wiring. I talked to the factory and they sent me a few partial diagrams which should help but not most of it. I still have the gauges, fuse block...