Have you look at a FSM wiring schematic yet ? If not look at one so you know about which wires feed the field on your alterantor
One is from the ignition switch and the other is from the ignition ballast resistor which is fed from the ignition switch
If you don't want melted wires find out what is ( loose wires, bad connection, corrosion)causing the voltage drop between the dash and engine wiring harnesses and fix it !
I've had to fix a bunch of burnt up wiring harness in many Mopar cars I've owned, the factory wiring and assembly of those cars suck
The old cars, pre OTB-1, have very simple circuits, no magic in them at all, battery and ground only except inside the alternators