Let them pull your fuel tank... have it "rebuilt" it shouldn't cost too much but it's worth it. my '76 tank had completely deteriorated internally and was preventing "normal" fuel flow... thus the fuel starvation symptoms. The valve from your charcoal canister should be the purge valve. I don't know if the canister can be cleaned or not, but they usually don't contribute to many problems. I'll bet on the gas tank a hundred times as your problem before I'd even play with the charcoal can.
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