Have you considered using the actual auto-paint? One of our Ariels (A-24) was painted "Cadillac Yellow" many years ago by a PPO and looked pretty good. Not sure how well it has held up, and I don't know anything about paints, but it seems like auto-paint is made to stand up to some pretty harsh environments.

On another note, Tim Lackey used Alexseal Snow White on his Daysailor project. I was fortunate to see it in person, because pictures just don't do it justice. But the gloss and depth of that paint job was simply incredible - almost 3-dimensional. Very very impressive, and looked very classy with all the woodwork too. He also painted a friend's boat dark green and said that looked really nice too.

I have no doubt that Ebb's Little Gull is equally impressive...