I have a 1986 F250 that ran great until yesterday. While driving it it started missing and then completely died. When I popped the hood I noticed a burnt wire that goes into an 8 block pin connector. The wires that are part of the problem is a red with lt green stripe and a yellow that goes into one section of the connector and connects to a red and red with lt grreen stripe on the engine wiring harness side.Previously someone bypassed the connector and connected the yellow and red with green stripe to the red and red with green stripe with a fuseable link. A sloppy job but had no problems previously. I don't know much about the diesel engine electrics but I'm thinking of some component failure, maybe glow plug controller. injection pump shutoff solenoid?

If anyone can point me in the right direction it would be appreciated. Also any advice on upgrading this system and the necessary parts required