Like many Roadster owners, I have both a UMC and the standard 120 volt "spare" mobile connector. The UMC can handle 120 volts via an ahttp://www.teslamotors.com/roadster/charging/universal-mobile-connector, but do I need to spend the $100? I've created adapters from dryer outlets to NEMA 14-50 for pretty cheap, since those are straightforward to wire. I then need to manually limit the current I draw. For 110/120 volt operation, however, what is the wiring like? If I pin the ground wire to ground, and neutral to neutral, then which of the two remaining wires gets the 110 volt "hot"? Or, is it that I pin ground to both ground and neutral and then connect the two 110 volt wires to the two usually 220 volt wires? I don't know that I'm actually going to do this, but it would make sense to not have to carry both the UMC and spare mobile connector when traveling in J1772-less areas.