Is your F-150 waterproof? No? PERFECT. Put some big, paddly tires on it, snorkel the intake through the ceiling (just use some duct tape and venting pipe), and boom. The ocean is now your domain. For about 30 minutes.
When you decide to sell it, just remember to leave out the bit where you were Captain of the SS Ford BoatTruck. A noble vessel if ever there was one.
