Duster Dash Mystery- Name that missing item.

In Canada, many dealers were charging extra and installing "econometers" that simply lit a light when you stepped too hard on the gas. A hokey rip-off for sure but folks were game to try and save gas.

I can't remember how they were wired exactly but it picked up a signal from something when you stuck your foot in it. Electronic Ignition? Maybe a solenoid they installed in the carb linkage?

Anyone else remember?

pete