Re: trim guage install
The trim sender lead is likely already under your console. I don't know what color it might be but look for a terminated lead - Likely bundled up with other wires and secured with a wire tie. If you find a suspect, use a multi-tester to first check it for 12V. If it's not hot then change your multi-tester to ohms set to 100-200 range. As someone moves the lever on the sender back and forth through it's range check to see if the ohms are changing on the tester. If so you've found the sender lead. That plus 12V power and ground for the light is all you need for the wiring.
