No Speedo (?) after Ignition Switch Replacement
 

So I decided to replace the stock, keyed ignition switch on the '87 track car with a Longacre switch/starter button assembly. I didn't want to have the potential of the steering wheel locking at an inopportune moment on the track.

Well, I tied the 2 red "constant 12V" wires together, and this feeds the input to the power switch. The yellow wire goes to the starter solenoid, and the rest of the wires were tied together and hooked to the output of the power switch. When the switch is "on", the car starts and runs normally when the starter button is pressed, and all guages (and the brake lights) work just as they should, except the speedometer (?).

This is a track-only car so it is on a trailer and not registered to run on the street. Therefore, as a check, I jacked up the rear end and put the car in gear, and there was absolutely no movement of the speedometer needle.

Questions:
1) Should the speedometer work if the rear of the car is jacked up, it is put in gear and the throttle is revved?
2) I believe that the speedometer is electronically controlled, so is there some wire that I missed tieing into the power circuit?
3) Where is the speed pick-up or sensor which feeds the speedometer?

Thanks for any assistance,
Tom