This is a little late but, The tach wire is located at the two pin blug at the dizzy it will be the blue wire, it is also located at the grey plug by the driver side firewall. (and of course behind the guage cluster and on the ecu) The way to test this wire is to start the car and hook up your volt meter, Place it on the AC current setting, you should read about 5-6 and it will change according to rmps. any more questions about wires just pm me, i'd be glad to help