I have a another vintage car with a Holley that has none of these problems, and we have WIDELY varied weather. My old style 1850 carb starts quicker than any of the fuel injected cars we have. Once in a while, in moderate weather, I have a high initial idle until it has run 30 seconds, but by then the choke coil is warmed up and the choke kicks off. If you insist on going manual, Holley has conv. kits to go to electric or manual choke. I think the choke housing gets replaced. SO, if Edel, does not offer the kit, they are right about some serious mods on the electric choke area. To fix it, 1 .Check for a FULL 12 V power supply- not the ignition resistor wire!!!!, and 2. a good ground. 3. Clean the choke and cheeck for ANY binding. 4. There should be two adjustments, anad it is not just the flap that works on a choke! - one sets how tightly the choke flap spring is set and the other is for how high the high idle cam holds the choke open. The cam adjustment may be hard to get to, but may help your problem.
With paitence your Edelbrock should be better than my old style Holley. Once fixed, you will NOT want a cable to mess with.