Wiring issues on 1996 Ford F-250

Ok my father was working on an issue with his brake light switch wiring where some wires had melted together and now he is having problems with getting the truck to shift out of low gear. Can you help me figure something out? I have searched the net several times because we are both stumped.

Asked by for the 1996 Ford F-250
here is repair manual site, need to repair the wiring.