I don't have the tank yet, but from the instructions it appears the TT Tank vent is led to a tee with the main tank and then routed to the canister. There is a one way check valve also involved that is between the tanks but I can't figure it out exactly. It will likely make more sense when I do the install. The main thing is you don't want the main tank overfilled. Surplus fuel will go to the canister or to the ground if there is no cannister.
Racing Blue, Premium Group, DWA