The comments about British automotive electrical systems made me remember this.
My company Gunny had a neat old MGB that he loved to tinker with. A couple of us who enjoyed cars would go over to where his family lived in base housing. We'd spend Sundays wrenching on it. He'd grill burgers for us, or his wife (from southern Alabama) would make fried chicken, mashed potatoes and gravy. After all the work was done, we'd sit in the backyard and polish off a couple of Stroh's.
We found doors, side mirrors and a bunch of other items in salvage yards all over Southern California. But the weak link was always the stupid wiring, that would short out and burn stuff up.
Our Gunny managed to actually track down a copy of the factory wiring system documents. We rode down to Tustin, where the Marine Corps had a helicopter base at the time. Two cases of liquor and three cases of beer later, we had a beautifully-made wiring harness for the MGB. Imagine three airframe mechanics building you a custom wiring harness with extremely high-quality parts, and then "loaning" you some test equipment to make sure you installed it correctly.
We installed it, and that car fired up and ran like a spotted-ass ape.
The last bit was hand-sanding down all the fenders and bodywork, and then repainting it in British Racing green. It took a while to scrounge the right colors to mix the green paint. More whiskey and beer were needed for the paintjob. The Motor T shop may have been involved.
Somewhere, I have a picture of the six of us standing next to that car. We fixed it just before we all went on a WestPac. It was beautiful.
That car epitomized the slogan "Ride it like you stole it."
Because we kinda did.