Dropped my cap into the drink while I was fueling up today (the retention chain had come unscrewed), and am looking for a clue as to what make and model stainless cap was used on the 2000' C310. I bought a Sea Dog brand that screws in and seals OK, but it doesn't sit flush like the old one. I checked the archives but couldn't find anything to help. I may go down tommorow and check the water fill to see if it has any markings.