Are you talking about the one gallon jug you take to the field to fuel your airplane? Yes, I have modified a cap where I've taken off the outside safety cap portion and drilled holes for two 1/8 brass tubes that I soldered to a brass strip then epoxied the whole assembly into the to the top ledge of the remaining cap. Mark in some manner so you can identify the fuel line to the bottom from the vent. And I move it to the next new fuel gallon.