I just made a quick draw up of the wiring for the electric gauge to help anyone out who needs it. It's pretty simple. The fuse splitter is in the position of the seat heater fuse and runs to the red from the sensor, and the red and the orange from the gauge. The black goes to the ground which is pretty easily visible with a flashlight just above the fuse box and forwards a little bit. The grey wire in the picture is the white wire from the sensor which connects to the gauges green wire.
Hope that helps. Let me know if you have any questions.