Will the Dawn work for the nasty grease and oil on the fiberglass in the engine room, too? I know my boat is 34 years old, but the sheer amount of filth on the sides and bottom in there is mind-boggling; apparently nobody ever wiped anything off at any time during its entire life. I think most of the "boat smell" I have is from old grease buildup and not my bilge water.
I'm thinking I can spray something on the sides and bottom in there, then reach in with a sponge mop or brush and scrub it off, then rinse everything into the bilge and pump it out with my vacuum extractor that I use for oil changes. Does that sound like it will work?