Does the engine start once it stalls, even briefly, when a splash of gas is put into the carburetor throat? If not (or if you haven't tried that) all this conversation about carb rebuilding is premature and a big waste of effort. I'm going to make one more suggestion and then let my frustration take over and stop reading this thread.
Your symptoms are very much suggestive of hydraulic lifters that are pumping up and holding the valves open. The best, brand new, original equipment carburetor that rolled off the assembly line when the engine was new can't provide fuel to an engine without manifold vacuum and/or compression. Even slightly open valves will kill both.
Goodbye and good luck!
Jerry
