Installing Remote start

I'm installing an Audiovox remote starter in my 2001 Silverado. One of the required connections is for "Tach Sensor input". Does anyone know where to make this connection? I understand it can be found in the PCM, but which of the 100+ wires?
Your assistance is greatly appreciated...Paul

the easiest place to get the tach is off the fuel injectors. u can use any injector just use the uncommon wire on all of them. each should have 2 wires and 1 wire on each one will be the same as the other injector, and use the 1 wire that is different on any injector.

another side not make sure that you hook up the 2nd ignition wire or you can ruin the trans. somehow on the gm trucks and suvs.

you may already have all this but someone else may need it someday. all the main wires needed for a alarm/remotestarter.
12volts red + ignition harness
Starter yellow + ignition harness
Ignition pink + ignition harness
Second Ignition white + ignition harness
Accessory orange + ignition harness
Power Lock lt. blue + brown plug at BCM
Power Unlock white + brown plug at BCM
Parking Lights+ brown + lt. blue plug at bcm or at headlight switch
Door Trigger - at dome light white wire
Tachometer white ECM
Wait to start dk. blue - instrument cluster
Brake Wire white + brake pedal switch
Horn Trigger black - brown plug at BCM

You really dont need to connect the TACH wire do you? Its been so long on mine that I dont remember if I did. I forgot what it does.

You really dont need to connect the TACH wire do you? Its been so long on mine that I dont remember if I did. I forgot what it does.

some remote starts require it and some have it optional. the vehicle will usually start smoother with the tach hooked up.