Need (1) switched 12V to power it (2) black wire to ground (3) sense wire to coil neg primary post (same for points or electronic (black/yellow wire on the pentastar ECU pigtail for electronic). (4) another wire for the front face light. if 1 2 & 3 are OK then the tach is shot. EDIT I am assuming not MSD

Last edited by RapidRobert; 02/02/15 04:15 AM.
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