The ICE ignition coil power wires are in a great spot to use for my 'switched' 12v power to the main contactor. One side had slightly higher voltage than the other... so I used it. I WAS going to use the fuel pump relay slot, but a test wire indicated that there is some kind of built-in voltage regulator or something in the base socket that limits the voltage and it would not trip the contactor. The ignition coil wire works great.