If you have lost the ignition wire loop block for your Gen 1 Smiths tachometer during your restoration project, Accutach Co. has the solution for you. We have reproduced the plastic block so you can safely get your tachometer working again without the risk of ignition wire chafing resulting in a dangerous short circuit to the tachometer case.
The ignition wire loop is connected to the ignition switch on one side and the positive side of the coil on the other. In some cars, the direction of the current through the loop matters to the tachometer due to the dwell time. If you find your tachometer is not working correctly after installing the loop block, swap the sides of the loop that go to the ignition switch and coil positive terminal.