Gasoline smell

[Kajtek1]

I keep my T in the garage and lately winds coming from garage door direction blow gasoline fumes inside the house, what was bad.
So I shut off gas at the tank bowl and drained both bowls.
That cut down the smell, but there is still some of it, what I take as tank fumes making it via unsealed cap.
Anybody tried to make better tank vent to clear the fumes?