Keep thinking, you got it figured out. The vent does both letting you fill with fuel and letting it draw out without collapsing the tank. I usually plumb the vent through a tipover valve
Jaz 834-206-06 - Jaz Products Fuel Cell External Tip Over Valves - Overview - SummitRacing.com and then a little compressed air muffler
McMaster-Carr on the end as high up as you can get it in a fenderwell. You can get a kit to do both tipover and vent from Summit, Speedway etc. Use flexible or rigid tubing to get from here to there.