Vapor Separator on carb-converted Alfa?

["Idleman, Christopher" <CIdleman@domain.elided>]

On SPICA-injected spiders, there is a hose that runs from the bottom of the
"vapor separator" (mounted on the passenger side near the front of the
engine bay) to a port on the airbox.  I presume that this is to allow fuel
vapor from the separator to be drawn back through the air intakes.  On cars
that have been converted to carbs, what is typically done with this line?
Is it plumbed into the carb air inlets (through the filter lids?), is it
plumbed into the fuel/vapor return line running back to the fuel tank, or
something else?  What is the standard configuration on factory-carbureted or
Euro-spec cars?

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