g16e no reverse. Wiring tampering

[Ajs]

Have been working on a 1997 yamaha g16 36V that's been sitting for awhile. prior to being parked reverse DID work. new batteries, new wires for bateries/motor, new f&r, fairly new solenoid and two new diodes. Everything is working but reverse. Solenoid clicks and buzzer goes off when switched to reverse. From the wiring diagram on cartoholics and signs of snipped wires there seems to be some previous tampering in its previous life. From the controller going to the throttle sensor the blue and brown wire have been disconnected. Also the yellow and black wire is coming from the small terminal on solenoid. Drawing indicates Y/b it is supposed to come from controller. Iv replaced just about every suspect corroded wire/connector.
Does anyone have any suggestions? . Iv spent more time than I would like to admit chasing this around.

[Ajs]

Have also found several spots wires were bent or broken. Would this cause anything downline to burn up? is there any tests I can do to narrow this down further? Can posts pictures if further details are needed. TY