firemarshal mike

Good morning everyone,
I am in need of your expertise. My son went to start his truck and it would not start. All he heard was a click at the solenoid. He noticed light smoke coming from under the hood. He called me and I cruised over to where he was broken down. All the wires at the solenoid, (positive side), had melted together into a nice big mess. I have 5 wires going to the positive side of the solenoid. 3 of the 5 wires have fusible links. Has anyone every run into this? I tried to bypass the solenoid with a screw driver and only got a click at the solenoid. The starter did not even attempt to turn over. We have had a problem with trying to start it in the past. It would act as if the battery was dying but would eventually start. Do you think I can replace the wiring after the fusible links or should I replace the wiring before the fusible links? I hate electrical, mainly because I know nothing about it except for the fact I know it can bite you really quick. Any advice would be appreciated.
1988 Ford F150
5.8L