Hard starting when cold

The orange box is junk from China (all the Mopar boxes are). Put the HEI upgrade on your to-do list. And speaking of the ignition: what (exact) distributor are you running, and what's your base timing set at?

Problems like this what you describe are usually down to a choke that isn't working properly and/or a loss of fuel in the carburetor overnight. First, what exactly is your choke setup? Is it stock Super Six equipment in good condition with all of the parts present and functional (including the electric choke heater controller)? Does your '72 have its original exhaust manifold, or was a different-year exhaust manifold installed? What (exact) carburetor is on it, purchased where? The next time the engine is stone-cold, remove the air cleaner lid. Hold the air cleaner housing firmly downward with your hand while you operate the throttle. Does the choke plate snap all the way closed, firmly but not violently? Next check is as Fury440 described, open the choke plate and operate the throttle again while looking down the carb throat: do you see a solid shot of fuel from the accelerator pump jet(s)?

Don't be misled into thinking an electric fuel pump is necessary or desirable. It's neither.