Yup. The way it works is when the carb is "down" to the hot (curb) idle, the throttle actuates a grounding switch. So the solenoid is hooked to "ignition run" on one terminal, and the carb switch on the other. When grounded....at idle....the timing retards for emissions.
You can find documentation in the emissions sections of the correct year service manuals, and you can download them at MyMopar
I believe they started these "on some engines" in '70 They were used on 440 4bbl (GTX) but my 440-6 did not have one. My car, however, was not a CA car