Installing a tachometer in a classic car that didn't come with one is a straightforward job if you choose the right type and route the signal correctly.

Electronic ignition systems require an electronic tachometer. Points systems work with mechanical-pulse tachs. The distinction matters — connecting the wrong type produces erratic readings or no reading at all.

Signal source: a points-system tach takes its signal from the negative terminal of the coil. An electronic ignition tach should connect at the same location if the conversion to electronic ignition preserved the traditional wiring layout, or to the tach output terminal if the electronic ignition module has one.

Mounting: the tachometer should be visible without obstructing the driver's view forward. A column-mount or A-pillar mount keeps the gauge accessible without cutting the dash.