I just put one in my car, on the A-pillar you can drill a hole, run the 3 wires down through your dash then the black is the ground, red needs to go to a 12v source, i just ran mine to the battery, then the green needs to be spliced with the tach wire in the ECU, which is the brown wire with a white stripe! theres a more detailed install at
http://www.newc elica.org/other/installs/shiftlight/index.htm
PM me if you have any more questions!