i wired my rev gauge without a diagram, if u take all the steering column plastics off to get to the wires, use a test lamp on the wires for the ignition barrel, there will be a permanent power feed to the ignition barrel. then find a wire that only comes live when you turn on the lights, this could take a while as im not sure how many wires there is. you can just take an earth from a near by body earth,either scotch lock all the wires on or solder them with heatshrink Gary