Vintage Connections has terminals, wire, and crimper for effecting your repairs in a professional manner. Recommend you replace the damaged wiring and solder joints you splice your repaired section. One option would be to open the harness to replace the entire run of that wire with new but that would require new sleeving and quite a bit of disassembly. Use a good quality heat shrink on your repairs if soldering your splices. A good quality heat shrink will have an adhesive inside the tubing which helps make the repair watertight, helping to lessen chances of wire corrosion because of moisture.