If the guage is in the car you should be able to get a bolt meter to the rear posts of the guages. One of the posts to ground should read about 5v. If not the IVR or the power to the IVR may be bad.
With some alligator clips and a 9 v battery you should be able to get needle movement.
NOTE CORRECT POLARITY IF STILL HOOKED UP TO CAR.
DO NOT HOOK 9V BATTERY SOLID TO LEADS JUST TOUCH MOMENTARILY OR YOU WILL DAMAGE GUAGE.
Forgot to mention rear of cluster shown is 67 thru 70 something.
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