Any yellow wire will give you 12 volts A/C power and any brown wire will give you natural or ground. The best way, I think, is to wire it is off of the voltage regulator. There is a empty plug on it (yellow wire) for accessories. Just hook the red wire on your harness to the yellow and ground the black to the frame (One of the hold down bolts on the regulator works for this).
Any yellow wire will give you 12 volts A/C power and any brown wire will give you natural or ground. The best way, I think, is to wire it is off of the voltage regulator. There is a empty plug on it (yellow wire) for accessories. Just hook the red wire on your harness to the yellow and ground the black to the frame (One of the hold down bolts on the regulator works for this).