{Chrysler 300} Why, oh Why? drivability question on Hurst

Admittedly, I neglected to drive my Hurst for almost a month (at least 3 weeks anyway), as weather and scheduling of car shows and cruises in warm/hot Texas has been more conducive to early morning 'cars and coffee' type events with the top down in the cool of the morning, and the G is my favorite.

I finally drove the Hurst this past weekend, and two symptoms I never had before popped up. Car starts normally on fast idle with cold start, and progresses down onto normal idle as always, but two things now happen that never happened before-

1. As I approach my street coming home (car fully up to temperature and running fine down the road), I have to slow almost to a stop and take a right turn into my slightly uphill street entrance, and the car shuts off like it's out of gas. If it doesn't stall, it stumbles quite a bit and I need to pump/feather the gas pedal to keep it running. If/when it does stall, I pop the gear shift lever into neutral and it fires right back up and proceeds up the hill to my driveway, where I make a left hand turn into the driveway on level ground with no issues. Then I pull into the garage, idling smoothly, and when I shut the car off it tries to run-on slightly before shutting off. It never did either of these things before I let it sit. Do I have a gummed up carb messing with float levels or needle/seat or jets? Settings on the carb float levels couldn't change just from sitting, right? Any guesses? Don't want to remove the carb and tear it down unless that is the only recommendation. I do have multiple carb kits with parts if I have to, or maybe I just put some gas treatment in the tank and run it for a few days and then reassess what's going on? Any suggestions appreciated.

I have noticed now that I'm in dry, dusty, central Texas that gas bowls run dry and linkages for choke and choke pull off need lubrication with gumout spray much more so than in cooler, more humid New England. I even had a PCV valve stick for the first time ever. Perhaps I need to put additives in the gas and make sure I drive everything more often?