I just thought of something that could cause the symptoms you describe. Although I'm still interested in knowing if any of the reg/rect wires are shorted to the case. After you check that remove the flasher unit for the blinkers and see if the problem continues. I think you have a power to ground short somewhere, of course finding it is the trick. I would take your gps out of the circuit for now so that it doesn't get hosed from all the power spikes. Also, is the 100w light blowing (10A) fuses?
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