[chipflyer]

I think I need to clarify the tach is hooked up and works but it's inaccurate and wont go past about 3200 rpm I'm told that is because it's hooked to hei and there is some kind of resistor or something you can put in the wire to the coil that will make the tach happy with hei.

Mine is also a bit inaccurate, it actually reads higher than it should as RPM's increase. I have done a little research and have found that the HEI tach signal is a digital signal and the old tachometers are analog device's that expect to receive an analog signal. They just don't work very well together but can be improved if you add a tach filter. If you do a google search you will find many examples and I have added a link to an ebay item that may help in your situation. I have wanted to try one of those myself, just haven't gotten around to it.

Monte Carlo Tach filter

Here is a link to good info over on the vette forum Tach filter