Figured it out, there's three wires as I stated one is ground BLACK easy enough, one is 12v RED switched ignition, and one is GREEN witch is the the signal. I found with the 5.0 it's easyiest to run a wire out under the hood to the coil next to the distributor, and splice in to the yellow wire or left wire on the 2 prong harness that plugs into the lower part of the coil, this is the negative. The shift light is a cheapo eBay LED adjustable one, and works exelent for the $19 I played for it. I also didnt glue or screw any holes in my dash, I just bent the bracket and clipped it onto the center console near the pedals where my legs won't hit it and aimed it up at my face. I'm contemplating dissecting the board out of it and hooking up a brighter auto meter mini or raptor tack light because the eBay one is not all that bright when the sun hits it, but at night it's obnoxious.