If you're searching for a custom made tachometer or you want to convert your instrument dial from "MPH" to "Km/h". Then you certainly need a custom printed tachometer to see your speed and rev's needle like you want it. 

How to program a new Key fob (Cobra alarm systems)

2. Press and hold both buttons on fob until FOB light stops flashing (about 10 seconds). Do this for all remotes to be programmed (Including the old ones). After this the light of the fob should stay on until after programming. This is the last step where the fob light matters, all else concerns the TACH light.

3. Turn ignition off and on three times fast (within 7 seconds) stop in the off position
The TACH light will illuminate for 3 seconds then go out.

4. Enter your alarm code as per the book. Basically turn on the ignition, count the number of flashes to correspond with the first number of the code and turn off the ignition. Do this for each number of the code. If the first number is correct, the system will continue flashing for the next number. If not the flash will stay off and you'll have to repeat from step 3.

5. After the last number is entered and you turn off the ignition you have to turn the ignition back on and if all goes well you should have a STEADY illuminated TACH light.

7. Press and hold the large key fob button on one of the remotes until the TACH light goes out then comes back on.

8. Turn off the ignition and check each fob for function.

That should do it and by the way if it does not work don't fear, after many unsuccessful, incorrect attempts, the original fob never lost its program and would still work.