Soaked plug one cylinder

[davecarney2]

6 year project 2003 6.0 from an SS Silverado with a 4L80e. Went to check for oil pressure etc prior to starting the first time and it locked with fluid. #6 cylinder plug soaked removed all plugs and the #6 blew gasoline everywhere out of the spark plug hole. Gasoline in the oil now to from filling the cylinder. I did run it for 20 seconds and it sounded fine but next day turned the key on and it filled the #6 again. Afraid to start engine again. Any advice on troubleshooting this would be greatly appreciated. So close to seeing the road with this thing.