Gizmo, can I persuade you not to paint the hulls? 1st, use Scotch Brite non-scratch scour pads to remove mold and mildew from the hulls, then use 800 or 1000 grit sanding waterpaper and remove the dead outer layer of the gelcoat that has oxidized, for the textured decks use barkeepers friend and a stiff brush, using water mix powder into a runny paste, when that is done, use either Poliglow, www.poliglow-int.net
or Zep Wet Look Floor Finish, from Lowes
both are acrylic based clearcoats that you just wipe on, after the 3rd or 4th coat your hulls will look like new.
The poliglow is a little more expensive but comes in a kit with the poliprep and the poliglow, but also with applicator and scrub pad. The poliprep is for removal of wax and crud but if you use waterpaper to remove oxidization, then you wont need the poliprep, then go with the Zep using Barkeepers friend to prep the textured surfaces. http://www.barkeepersfriend.com/fiberglass