Slight stumble when cold?

Hey everyone, ive noticed this winter that my 340 has developed a slight stumble or miss when the car is cold, once i drive it down the road 2-3 miles it clears up. I always let it idle for about 5 minutes or so before i drive it to allow the oil to get circulated and come up to temp. It has been about 7 years since the car has been built so maybe a carb adjust is in order? I tried i think last spring to adjust the idle air mixture and adjusted best i could with a vacuum gauge and the edelbrock manual along with help on here. It seems as though since the outside temp has been in the 50’s it seem to have the slight stumble. The stumble can be felt not really at idle just more or less with a load on the engine, almost like it surges. Its either a 650 or 700 cant remember eddy thunder series avs carb. Electric choke. Mopar chrome box. Just put new cap, rotor, plug wires and plugs in it last spring. I usually do plugs every 2 years. Change the fuel filters every year. Filter On top of the intake looks clean. Havent checked timing yet but it should still be at 16 degrees and all in at i believe 34. No vac advance. For about the first 3 miles it has a surge/ random stumble to it with a load. Not the point where you cant drive it but you can definitely feel it. It progressively goes away as i drive and by about 5-7 miles it runs great. Even did a wot pull from about 15 mph and it pulled through 1-3 no problem and you could feel the secondaries kick in and didnt hesitate at all. Just throwing me off. I dont ever recall having any stumble in the past that ive noticed. I know the ignition system is in good shape, i also keep 100% 93 in it but granted i only get to drive it about once or twice a month in the winter. Possible its bad gas? It was about 48-50 degrees out when i took it for a drive, not sure if the fuel was too cold? Any suggestions. I need to get with the engine builder and have him double check the idle air mixture and start from there. And maybe have him give the carb a good once over. I know i cant completely rule out the ignition module. I have a orange box i could swap in and try it to se if there is a change