I just though of another area you may want to clean up after having the frame powdercoated .
The main grounding or earthing point for most of the circuits, is one of the mounting screws that secure the voltage regulator to the frame, make sure the threads are free of powdercoat .
I never liked this arrangement for a major ground, I added a heavy gauge wire from this point, back to the negative terminal on the battery, just a thought .