klipzracer is 100% correct, you don't have to send it back to automemter if you hook it up to the right wire (solid white wire going to the PCM)
I am sorry I don't have a diagram, but it's hella easy to find the wires I was talking about.
you will need a volt meter or test light to find the wires.
You will find 4 wires behind your cigarette lighter 2 wires going to the actual cigarette lighter, and another 2 wires going to the bulb that lights the cigarette lighter up.
Take one of the wires that goes to the actual one and hook it up to your volt meter or test light, turn the ignition key to on position, if you get 12Vs from that wire, then that's the wire to hook up to the red wire that goes to your new tach, if not, then it's gotta be the other wire.
now you see those 2 wires going to the bulb that goes in the cigarette lighter, take one of them and hook it up to your volt meter or test light, turbo your lights on, if you get 12Vs from this wire, then this where you hook up the white wire going to your automemter tach, if you don't get 12V from that wire, then it's gotta be the other wire going to the same bulb.
the green wire goes to the solid white wire going to your ECU as I said b4 (the only solid white wire, you can't miss it)
ground is easy, I am sure you can do that on your own.
Where to run the wires from or 2 depends on where your tach is going to be mounted.
