Hello and welcome to just answer Dodge. I am thinking of 2 possible things here. 1 the carburetor idle circuits still have a problem, (blockage, air leak, etc.) or, if this engine has an EGR valve, it may be stuck open and will cause a die out at idle. One way to check for an EGR valve, is to disconnect the vacuum line to the valve and then see if the engine will idle. If not, then start a cold engine, keep the throttle open enough to keep it running, and then feel the EGR valve. If it starts to warm up, then it is stuck open mechanically and will need to be replaced. Do this last test with the vacuum line still disconnected.
Hope this helps, and let me know what you find,