I have agree with @dutchzcarguy some. I recently was helping a local owner he drove my car then said wish mine ran this well. I drove his it just seem sluggish. I had him do a valve adjustment and he discovered that he had low compression on two cylinders. So he pulled the head and found the head had a crack and bent valves. They were not closing all the way.
So if you haven’t, test compression, adjust the valves, test compression again if needed, check distributor ignition system, check timing, check for plugged filter, check for vacuum leaks, check fuel pressure, unhook all of the throttle linkage. Make sure is opening al the way. No binding or stops. Once you are at this point I would mail those carbs to Ztherapy.
I know it frustrating, but you will find the problem. Them you will love that car.