8 Two wires come with the main Rally-Pac harness that you can disconnect and install separately of the Rally-Pac. One is the power feed from the ignition switch and the second is the tachometer signal wire. The short black wire connects to the stud on the back of the ignition switch. Temporarily remove the retaining nut, then slide the ring terminal of the short black wire over the stud and re-secure the nut. Now you can reinstall the gauge cluster and kick-panel trim.