RE: Prepping the Bilge for Paint?
I've used Simple Green to clean up dirty, oily things like engines and such, and I used it to clean our anchor locker prior to painting (which was dirty but not oily). But you have to make sure to get the soapy residue off completely. I've found it to be pretty effective when the oil gunk residue was not too heavy. There are all sorts of bilge-cleaning products on the market, however, so I'm sure there are a fair number that actually work. You might try a Google search with something like "bilge cleaner reviews" or the like.