Autogauge Tach

Well I did some checking and heres what I found.

At the ballast resistor with the car running I have 14.19-13.82 volts on one side and 8.13-7.84 on the other side. With the car off I have 1.1 ohms across the ballast resistor.
With the car running I have 7.94-7.54 on the positive side of the coil.
I got no reading with the tach wire to ground.
So it appears that my ignition system is ok. I guess the ECU could be acting up, but it never has until the tach was installed. And the instructions stated that the tach was ok to use on Mopar ignition systems. The FBO system I'm using is about the same as a Mopar system.

I only have a week or so to figure it out before my 90 days are up on returning it.