1 Answer

Things You'll Need
Drill
Hole saw
Small adjustable wrench
Screwdriver

Instructions
1
Check beneath the dash to ensure that no under-dash wiring will be damaged when you drill the holes in the dash for the tachometer and its mounting screws. Mark the locations for the hole for the tachometer's installation and mounting screws using the template provided with the tachometer. If wiring can be moved to one side, do so and tape it out of the way with duct tape.

2
Cut the hole for the tachometer with an appropriately-sized hole saw and drill the screw holes in the dash with the appropriate bit.

3

Remove the nut from the post of the switch that controls your navigation lights with a small adjustable wrench. Push the wires from the tachometer down through the hole in the dash for the tachometer.

4
Wrap the light gray wire from the tachometer clockwise around the post of the navigation light switch. Thread the nut back onto the post and tighten it.

5
Loosen one of the screws on the common ground. Wrap the dark gray wire clockwise around the screw and tighten it with a screwdriver. Connect the yellow wire to the terminal for the breaker points on the motor's distributor. Lower the tachometer into its mounting hole and secure it in place with the screws provided with it.

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