Frankly if I had an Evap controlled car---and did not care about "restore correct" and did not have to argue with a state emission program, I would modify the filler neck to act as the 69/ earlier vent system. The one problem with this is, that due to the vent tube, the 69/ earlier tubes must be installed from the trunk before the tank is connected, and the EVAP models can be shoved in from the outside. You could brase a flush or nearly flush fitting into the tube that would slip through the fender hole.
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