Bosch tach not working with Mopar Performance Electronic Ignition

[youngcuda]

Just bought a Bosch tach to column install on my 70 Gran Coupe.  Hooked it up under the hood for a test and the tach indicator moves off zero only a fraction and does not respond to any increase in RPM's.  I have a Mopar Performance Electronic Ignition kit installed, an Electronic Voltage Regulator (my 70 383 was not an Electronic Ignition vehicle), and a standard coil.  The engine runs great.  I hooked up the green tach wire to the negative post on the coil as instructed, with red to battery positive and black to battery negative.  Does anyone know if the green wire should be connected differently?