Most trucks today come with a tachometer already installed, so the need for a big, massive thing bolted to the dash is kind of redundant. Missed shifts lose races, but more importantly, they can cause the motor to go "boom." So it's good to keep tabs on the rpm.
If you've modified the motor so that it twists higher than the factory intended, or you just want more status, then you might need an aftermarket tach. If you're like us and want one of the other cool features that is usually the norm on these aftermarket tachs, Proform has it.
Proform Parts recently introduced its stand-alone, 3,000-to-11,000-rpm shift light. The shift light does not require a separate module and allows you to set shift points via a dial on the back. Basically, the shift light comes on at a certain rpm to let you know when to push in the clutch and grab the next gear without taking your eyes off the road. We went to Circuit City in Buena Park, California, to have Brandon Smith, the road-shop manager, throw it in. If you didn't know Circuit City does more than simple stereo installs, check out the Web site. If you're ready to see the light, then get your shift together and read on.
1 & 2. Here is the light from Proform. It works with just about all four-, six-, and eight-cylinder applications and doesn't require anything more than a few screws and some time to install. |  |
3. The first thing to do is find your location. We chose to put it right next to the boost gauge. Make sure to leave enough room to adjust the dial on the back. | 
4. A couple of self-tapping screws hold the base to the dash. |
5. Three wires need to be hooked up: a power, a ground, and the signal wire that picks up the tach signal. Wiring diagrams cover most trucks in the instructions. We ran the wires down the pillar and picked up our power and ground from under the dash. The green wire was run out into the engine bay through a small hole in the firewall. | 
6. For our Toyota Tacoma, we had to find the green wire with the black stripe coming out of the ignition igniter located on the passenger fenderwell. (Special thanks go out to Ron Crown for that information.) Brandon checked the wire first with a multimeter just to be safe. |
7. After Brandon made sure it was right, the green wire from the light was spliced in and the connection soldered. | 
8. All we had to do now was turn the dial to our desired rpm point and go out and bang some gears. |