I can't believe nobody mentioned this. What gauge wire were you running current through? Too much electricity through to thin a wire will get stuff hot enough to burn. Quick,fast, and in a hurry.
The wire in question is the OEM wiring. I usually use 14awg wire when I replace wires that were melted.
I am not a virgin when it comes to electrical circuits. Before I retired, I was an electrical engineer.
My main problems is the car does not match the schematics I have and/or the schematics I have are incorrect.