Are you 100% sure that this is carb related?
i had a similar problem with my mustang a few months ago. Left to go home from work and it stalled. But then it started right back up but was a littel hesitant. Drove about a mile and off she went again. This time it was a bit harder to start but it did finally fire after I cranked and pumped and cranked and pumped. Drove to the next light, about 1/2 mile and off she went again. The whole time kinda hesitating when I gave her throttle. I pushed her into the parking lot of the parts store right there and guessed right away.. fuel pump or filter. Ran inside and got a filter and that did nothing. Put 5 gallons of gas in it and nothing. The pump (electric holley red) sounded kinda weak. I had plans that night so I left it there overnight. Finished the last 1.5 miles in the morning being pushed by a truck. I did a bunch of troubleshooting with the carb and fuel lines and finally dropped the gas tank to check the pump. What was the problem... the pickup in the tank used a rubber hose. the hose had split and the car was getting that.. "sucking through a brocken straw" effect. Which is why it would start but not stay running once the secondaries were pumped out. What a pain! A gas tank is heavy when it's 1/2 full!!
I put a new piece of hose on and she fired right up and the pump came alive!