Len,
I just got done looking at the instructions ( at Summit Racing ), and there are 3 primary wires.
BLACK- Ground. Goes specifically to the " - " negative post on the battery.
RED- Connect the RED wire to any vehicle harness wire which is energized
with battery voltage ONLY when the ignition key is in the ON (RUN)
position, NOT OFF or ACCESSORIES.
WHITE- Interior lighting. Hook up this to the "gray" wires that feed into the
back side of the speedometer housing cluster.
GREEN- Connect the GREEN wire to the negative (-) side of the ignition coil. This
terminal may also be referred to as the TACH, TACH TEST, DEC, or ECU terminal.
As for your application, you have the "stock" wiring harness, correct? Just re-check your connections
Dan