Good morning, I have all stock wiring in my 49' from 1949.... with the exception of some hack job shit. I plan on getting the engine bay dustless blasted and painting it with POR15. Wiring being operational but shot.... I was thinking I want to but the O.G. harness for the engine bay. I want to eventually swap from 6v Positive GND to 12v Negitive GND Does anyone see an issue with this wiring or an issue I may run into with the swap later?