> At this point I am open to any and all suggestions as to what
> to do next.
IMO, you've still got a fuel passage somewhere that is nearly blocked. It
takes only a tiny amount of air (and fuel) for the engine to idle, so the
only unusual part is that it takes nearly full manifold vacuum to pull
enough fuel through the jet.
I went through something similar with a stored lawnmower, seems that what
they sell for gasoline in CA these days dries to a hard white substance that
"carb cleaner" will not touch.
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