Test Mode (holding the trip reset button while starting engine) is also quite handy if you accidentally remove needles when installing a guage face...all you need to know is what your gas was at. It's tricky, but what I did was warm up the car, with my gas light just come on. I put engine temp at middle, and gas just grazing the empty line. The hard part is setting the speedo and tach, cause the car has to be moving obviously, but on a nice straight level road setting needles at 15 mph shouldnt be too hard. Test mode sure is handy!
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