I found a molded hose that connects the charcoal vapor can to the air cleaner. Its inside diameter works well with both the vapor can and the air cleaner adaptor. It is Dayco 80413 ($11) and can be cut to fit. The original parts from Ford are no longer available except on eBay or similar maybe. One of the Mustang parts vendors has the adaptor (used) at the end of the new hose below for $30.
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