The only thing common between the clock and the gas/temp gauge is the cluster ground. Make sure the gauge cluster has all of the ground connections to good clean grounds. Are you sure the clock is supposed to work. 90% of them don't and they get power from a different circuit than the other gauges. Try attaching a wire to a good solid chassis ground and tie the other end to the metal gauge cluster case.
Steve Strasemeier (70SS 396, Fathom Blue/White Stripes) My 70SS
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