OK, during a spin in my 68 today, there was an overwhelming smell of gasoline when the windows were open. I first (fire extingusher in hand) checked the engine bay, but no leaks or smell. No smell anywhere when it was parked and no smell with the windows up either. No dripping and all the lines are dry...so what could it be?

gas cap?
some vent line in the luggage compartment??
other???