No OEM AVS used any kind of elec choke mechanism, but the current aftermarket AVS, AVS2, and AFB can be had with or without an integral electric choke. By 1970, the well the thermostat went it was a separate item and made of stainless steel to heat the thermostat quicker so the choke would come off quicker, for decreased emissions, which is good. Rather than the prior cast iron well which probably took a while longer to get hot.
In the case of the carb solenoid, it was probably a carb idle solenoid. Two uses, possibly . . . one is to set the idle with an energized solenoid so that when the electricity stops, the throttle goes to a lesser idle speed so the engine will stop quickly. On some engines, the hot idle speed was over 800rpm and the engine would "diesel" when the ignition was turned off, otherwise. The other use might have been to increase the idle speed a bit when the a/c compressor was in use? But not all vehicles used them, so a loose connector was not connected to anything.
Just some thoguhts,
CBODY67