89 Ford Probe Tach Wire?

Anybody have any idea where i can find the Tach wire on an 89 ford probe. i looked everywhere. i got the chart off of this website and i cant find the wire at the coil that is the yellow/blue and i looked under the drivers kick panel and found a YELLOW /GREEN wire that was coming from near the rpm display but when i hooked up the tach wire from the alarm and put it through the testing it keeps giving a engine already started beep and it won't learn the rpms. any idea about this wire and where it is

Tach is YELLOW /GREEN at the coil... Put a multimeter on it, set ur meter to ac volts probe the YELLOW /GREEN wire with the red lead, attach the black lead to ground, should read from 1-6V AC, rev the engine, voltage should go up accordingly, that's the wire you need.

I ALMOST never use the tach wire well sometimes but i do alot of remote start installs and the best place that works all the time is the uncommon colored wire at one of the injectors look at all the injectors and use the uncommon color. i hate ebay they are stealing my business