got a tach, need to know what wires do what

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ok i picked up a autometer sport comp 5 in tach. i got it used so naturally it didnt come with any instructions, and i just need to know what wires do what. theres a red wire, a green wire, a black wire, and a white wire. theres also some smaller wires 2 light blue and 2 brown. im thinking maybe the smaller wires are for the 4 or 8 cylinder setting? right now the two brown are hooked together and the 2 blue are not. so what wires do what? anyone have the instructions?
nevermind, i got instructions from their site, but one thing im confused about is on their site they say the loops are brown and qroance, mines brown and blue. is this nothing? am i fine?
also should i hook the tach directly to the (-)neg terminal on the coil or will hooking into the blue wire be just as good? same for the engine ground, should i go all the way out to the engine as specified by the directions? or will an in-chassis ground be just as good?


Rest In Peace
the older tachs used to have a brown and orange wire that you cut for 4 cyl. the newer models have a brown and blue wire that you cut.
red wire - ign power
black wire - ground
white wire - light
green wire - tach signal
best way I found to hook up the tach wire is to take a test light and hook the clip to the green wire and use the test light to find the wire that gives you the tach signal. once found connect the green wire to the wire that gave you signal
for the ground wire no need to run the wire into the engine bay hust find a ground point under the dash.
power wire - just find an wire that has power when the ignition is on
light wire - splice it into the wire on your dimmer switch that gives you power when you turn on the lights

also I not sure what car your putting that into, but I know that 92-00 civics have a blue wire with a plug on it on the drivers side wiring harness that is the tach wire