My bracket that bolts to the right side rear head and has the main plug with a relay and a breaker is +12v, the whole bracket is positive. It does have the plastic isolators installed but this doesn't seem right at all.

It's reading positive because you have a weak ground. You have to make sure all your ground wires are clean, tight, metal to metal connections with no paint or corrosion.

i think you also have a short between main power wire and that bracket. it needs to be grounded, but you shouldn't see volts on it.

It was a wire touching the metal part of the relay. Dont know how it didn't screw something up but fixed now.