How do I wire up a new Teleflex tach for my 1968 Merc 500 SS with Thunderbolt ignition? <br /><br />Teleflex said their tachs will work with series 2 or newer Thunderbolt systems and not with series 1 systems. Although I have the original owners manual as well as the Mercury service manual I'm unable to determine which series I have. I spoke with Mercury last week and they were not able to help me; in fact the "old timers" said they never heard reference made to different series Thunderbolt systems.<br /><br />I have the three-lead tach wiring harness with white (instrument light), brown, and black wires. <br /><br />Anyone know how to identify the ignition systems series and/or how to wire up the tach?<br /><br />Thanks!
