Hi guys,
I went to the lake today to install my new mooring cover. The boat has been sitting since October on a lift in a covered dock with the snap-in bow and cockpit covers installed. When i pulled the cockpit cover I was greeted by the staining in the attached picture. The stains are isolated to the area where the cockpit cover rests on the very back of the boat. I tried to clean this with 303 cleaner and also a magic eraser but nothing would touch it. Anybody know what would have caused this staining? Anybody have any ideas about what might clean it? Thanks in advance for your help.

I went to the lake today to install my new mooring cover. The boat has been sitting since October on a lift in a covered dock with the snap-in bow and cockpit covers installed. When i pulled the cockpit cover I was greeted by the staining in the attached picture. The stains are isolated to the area where the cockpit cover rests on the very back of the boat. I tried to clean this with 303 cleaner and also a magic eraser but nothing would touch it. Anybody know what would have caused this staining? Anybody have any ideas about what might clean it? Thanks in advance for your help.
