Installing tach...doesn\'t work? I bought a new tach today and have everything hooked up and it is not working. I have a red, green, black, and white wire. The red is feed into the fuse box, the black ground, and the green is feed right to the distributor. The white is for light control. It is a suncraft or sunpro brand. The instructions state that you must have the power installed to a acc that only comes on in the run position. Not off or accessory. Does anyone know which one I could use?