Tank venting valve

One of the reasons of MoT failure was a fuel leakage. On the top of the tank, I put some teflon tape on the threads of the fuel return line connection and the tank venting valve. Additionally, I connected a small piece of hose to the latter and guided it into the rollcage. The lower connection where the fuel is picked from the pump can only be taped when the tank is empty. For now I gave one more spin to the screwcap. Maybe this is enough, else I will drive as much as I can to empty the tank.
Cheers.