O.K. Just got off the phone with Firebird Central and they told me that since this car was not born with Rally Gauges, it would require a whole new engine harness, headlight harness and printed circuit to make the tach work. They suggested that I could buy the tach, new printed circuit and tach harness, and make it work (i.e. it will physically accept the mounting of the new tach and the clock will work) but that it would require getting power and a ground to the tach, and then running a wire to the HEI distributor for the tach to work.
The car had an aftermarket tach on the steering column, but a previous owner removed it. I'm pretty sure that the green wire in the photo below was the lead from the distributor to that tach. So, my question is, how should this new tach be wired to make it work properly? I've provided links below to the items they recommended that I buy.
Tachometer
http://www.firebirdcentral.com/Searc...earch=DAS-2012
Printed Circuit
http://www.firebirdcentral.com/Searc...arch=DAS-2311A
Tachometer Harness
https://www.firebirdcentral.com/Sear...earch=WIR-2352
Gauge Lens Kit
https://www.firebirdcentral.com/Sear...earch=DAS-2061
Tach Wire in Engine Compartment
Thanks,
BJ