[Rickertsen2]

I think i can help you with this. I don't know much about cars, but i know a bit about electronics. The first step would be to figure out the pulses. do you have an analog multimeter? Connect it between a ground and the signal wire to the tachometer. What happens as the RPMs go up and down? A digital meter may work, but im not sure. as long as the pulses have a duty cycle or in the case of PFM or PCM, a frequency that varies linerly with RPMs, a simple RC circuit can be used to filter them to a DC voltage. I think i can help you design a simple circuit to filter the pulses and drive the LEDs, using cheap radio shack parts. A basic Stamp is way overkill, and not needed. If you want to learn more about electronics for yourself, i would highly recomend a book called "pracital electronics for inventors" as a start.