Jimmy and Kathryn Merriman had a messy idea when the economy hit rock bottom four years ago. They built a 150-foot mud pit behind their house.Now four years after their first mud bog on July 5, 2008, the Merrimans are regularly drawing around 1,000 spectators to Centertown Mug Bog twice a month.“Bring a lawn chair and your appetite and we’ll take care of the rest,” said Kathryn. “Our slogan is come play in the mud.”And play in the mud they do as trucks of all shapes and sizes line up to forge their way through deep mud.