yes running another parallel wire in thru the bulkhead on each side for the 2 large feed wires as Nacho recommends is a good idea as the bulkhead connectors tend to corrode and those 2 circuits do flow alot of current. But I'm worried that you have alot more open and or poor/corroded connections (as evidenced by the hot/melted areas). There's some wiring diagrams at www.mymopar.com then click on tools on the left side then click on wiring diagrams.