Welcome aboard....Nice rare car that you have there. Congrats! This would be a good magazine article story.
Getting back to your original question....It does sound as if you have carburation problems. If not, I would suspect valves/heads. Drain the fuel entirely out of your system and start with fresh! Add av gas if you can find some along with the additive, but drain the old out first!
Year One should have the parts that you need. If you PM me, I know of someone that worked at the Chrysler Dealerships in the early to late 70's in the Chicago area as a mechanic and may be able to help you with getting the carbs rebuilt.
