If a wire was shorting to something, the lights would flicker or go out...not likely to dim or glow 'orange'. That's a lot more likely (regulator being ok) to be a resistant connection somewhere, ground OR power.
If possible, feel the connections you can get to to see if any of them are warm. They shouldn't be. If you find one that is, at least reseat the connection. At best, replace the connection with either a good quality crimp or solder a lesser quality crimp connection.
A bad solder job is at least as bad as a poor crimp connection. Too much heat will wick the solder up the wire making it less flexible and therefore more prone to breakage.
Insulate the connection with a piece of heat shrink to keep moisture and crud out.
Any place there is a ground-to-frame connection, take it off, clean it, make sure the frame is clean, put it back together with some anti-oxident grease.
Good luck. Wiring problems can be a pain.