I saw on Telly (think it was wheeler dealers?) they took an old wiring loom to a company and they built him a complete new one. Might be a better option than relying on old wiring? Mind u saying that I was speaking to a guy who used to work on old naval helicopters and I asked about the wiring on them and old planes and he pointed at one helicopter from the 70s (can't remember what model) and said that's still got the original wiring and all they do is plug one end into a computer every now and again and it tells them whether there's any shorts in any of the wires. If that can last then anythings possible! He even said some of the planes like u see on ice pilots etc from the 40s and 50s run the original wiring, just checked regularly in maintenance.