Find the source of the problem first. I'd suggest putting a "T" fitting into the flex line between the frame gas line and the fuel pump inlet, and take a test drive with the vacuum gauge connected to it. Just before it dies, the vacuum should go way up if the problem is in the tank. It's also possible you've got a clogged fuel filter, if you've got one between the fuel pump and the carburetor, and it takes it awhile to plug up tight enough to stall the engine.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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