Tach Wire

[joey_racer]

I am trying to help my friend put a aftermarket tach in his 91 GSX but I need to know what coil wire I tap into. What color of if someone know where I can get a diagram at. Thank You in Advance

[crazytrain_96]

it taps into the ground wire off the coil. I don't have my manual up from the shop though. Can't tell you which one it is