I had a similar issue. I smelled gas when it had been parked for a few hours or overnight, but it ran fine. Very gradually the smell increased and one day in the garage, my wife spotted what looked like a few drops of water. It was gas. The old fuel line had started to crack and split just under the hose clamp at the bottom of the tank. A quick trip to Autozone and $4 later a new fuel line stopped the leak and the gas smell.
05 Kingpin 50th anniversary edition- Totalled