2008 Silverado 5.3 FlexFuel. 95,000 miles. Oil changed like clockwork every 5,000 miles.

Before changing my oil today I did the old dip stick to the nose test only to find a strong odor of gasoline. The oil looks normal after 5,000 miles, black and more black. Since I smelled gas in the oil I went ahead and pulled the plugs for a visual inspection (plug tips were white in color and need changing as well) and the threads on the plugs have what looks like oil but again smells of gas. The oil / gas was more prominant from piston #1. I'm confused, anyone else have similar issues? Could these be related?