cold weather edelbrock

I think you should put your choke back to normal, if by "turned up several notches" you mean it was richened more. These carbs are kind of finicky as far as the choke goes and you might be giving it too much for too long. Remember, turning the black thermostat cover changes how far the choke closes and how long it takes for it to open completely. You might be making the choke stay closed more than it needs to.

Also you might want to try setting up your engine bay so your air cleaner can get warm underhood air, or even a "heat riser" setup like on stock Mopar engines with single or dual snorkel air cleaners. I have an open-element air cleaner on my 318 but I have no hood scoops or cold-air induction so the air going into the carb is never cold enough to ice it.