Stewart Warner Vintage Tach wiring help | The H.A.M.B. The black wire is easier . If there is a wiring problem you just replace the " black wire " Plus it's an old school 32 Roadster so there is only like 8 wires in the whole car . Pretty easy wiring job . I also saw the 766 sender option which make sense to me since the tach has a #765 on the back . HOW TO WIRE DIGITAL TACHOMETER - YouTube Here is how to wire the chinese digital tachometer . Stop A Screw On Lathe Chuck From Sticking & Wiring Installing Chinese Tachometer Set - Duration: 14:37. Steve Jordan 29,515 views.