Is there some kind of chemical I can buy to remove oxidation? I just picked up a couple of boats that look like they have been sitting for years and years. The oxidation is really bad. A friend was telling me to wetsand it first. What kind of sandpaper do you guys recommend? I`m thinking 2000 grit, and what about a block? Do I need a block or will my hand be good enough as back up? I need to get this done in 2 steps. Suggestions appreciated