Electrical problem found

[WB72]

The last time I drove my truck in the night was about three years ago. I remember the lights just going off. Yes, I did panic, I got her stopped and was just about to start checking around, I smelt a plastic melting smell. Just as quick as they went off, the lights started working again.

Now three years later, I am triing to get this unit back on the road, I found a melted wire that is about a foot from the instrument cluster that goes to the rear parking lights. If I just replace the wiring, will I have the same heat problem again?

Also when I have the rear wiring unplugged, the signal lights in the front blink faster than when the rear is plugged in, is this normal? I have electronic flashers (both signal and hazzards)installed.

If I replace the wiring, could I just splice into the harness that is still OK and go to the rear and slpice again to the rear connectors?