If you can't quite get it fixed, you might consider doing what a lot of people do with their 4100s...get a new aftermarket Holley or other, and keep that 4100 off to the side for when you later sell the car. 4100s are just prone to a lot of problems and the new carbs will make your car enjoyable to drive.
The first thing I would do would be to give the side of the carb a tap with the handle of a screwdriver to get the float unstuck. If that didn't work, I'd take the top off and see if the float is maladjusted. Try doing that with a damn Holley.
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