Im with you on that, I can relate to "chopped up electrics" on so many levels that I would have to get a group of people to count fingers (LOL)
I have seen some really stupid cut ups, Some were genius level - e.g. older BMW 318 and 320 had a condenser fan relay with built in fuse that evades most as its in a small trap door, the relay had a nice clipped on holder too - That fuse blows when debris gets stuck in the fan and the amps go up, This knucklehead wired a 22A round toyota relay (the worst piece of garbage ever made by man) in place of that and wrapped it in a used plastic bag to make it watertight, while forgetting that the hopelessly poor relay made by toyota/denso is aircooled. Cue melted wiring - also helped by the fact that the condenser fan sucks close to 40 amps when going full rpm.
My own VW Golf, when I bought it had a nice mouse nest of wiring that goes from near the battery to the alternator, it is supposed to have a 90A Bosch 2 wire alternator which self excites through the charging lamp circuit Someone installed a toyota one which requires switched power and as the front wiring was missing they literally hanged a bulb there in the engine room (epic level genius)
I installed its own alternator, very cheap from lawrence rd scrap market and made the missing loom myself in about 30 minutes without a wiring diagram as it only had 2 wires for the alternator, 2 for the AC compressor and 2 for the high temp AC cutoff and one grounding point - I fail to understand that a person who does this for his wage can be that bad.
the epic part was the main charging cable, it had aluminium wire strands that were corroded, the voltage loss with the alternator full fielded was about 5 volts.