Older Corvettes use a tachometer cable; these classic Corvettes were and are the most desirable of the breed. The cable on the first tachometers was not the best idea, though it did work well enough. The big problem to avoid is having the cable or gear in the distributor lock up. The tachometer essentially works the same as the speedometer in the car, except the tachometer is attached to the distributor drive.
Remove the steering column instrument panel lower cover, using the Phillips screwdriver. Lower the steering column by using the 9/16-inch socket and removing the nuts that secure the steering column to the instrument panel support.
Pull out all the Phillips screws securing the instrument panel to the dash. Pull out the instrument panel carefully, just far enough to get your hand behind the panel. Unscrew the tachometer cable from the back of the tachometer. Lift the hood and use the pliers to remove the tachometer cable on the distributor by unscrewing it from the distributor drive unit.
Pull out the cable from the engine side through the firewall. There is a bushing in the firewall that you must remove for the cable to come out. Use the screwdriver to assist it in coming out.
Insert the new cable from the engine side through the dash enough to get a hold on it from the inside. Continue by pulling it from the inside and directing it to the tachometer. Insert the cable in the tachometer, and thread the cap on. Push the instrument panel carefully back into place and install all the screws. Lift the steering column, and install and tighten the securing nuts.
Install the bushing into the firewall. Connect the tachometer cable to the distributor drive unit. The inner cable has a square end that you insert into the tachometer drive on the distributor. If the cable does not slide in, turn the cable by hand a small amount, and retry until it meshes with the drive unit.
