Fireworks under dash

Its my belief that 99% of these electrical problems stem from non factory add ons.
When we see pics of melted bulkhead connections, head light connecters, and such, we cant know what was the root cause.
I witnessed the cb radio era, the fog light era ( most of that was 100% junk in a box ), and the jukebox era which hasn't ended. So many of these cars have suffered through that and fender benders too. Contact lugs will snap off the back of the sealed beam bulbs, lighting wires get pinched, on and on.
Today we can add aftermarket throttle cables to the list of root causes. Good luck with it.