: I'm ready to paint my wife's Chuckanut and went to the store to buy
: paint. I thought I just needed exterior oil based paint, but all
: they had in Rustoleum was Enamel. What am I supposed to use?
: Enamel seems like it would be too brittle?

I'm not going out in the dark to look at my paint cans to see if the word enamel is used, but, basically, Rustoleum has oil based paints and water based paints - if you thin it with mineral spirits, instead of water, it's OK to use on the polyester. Other hardware store brands are the same.

And, I'll just throw this out there. A first layer of thinly spread PL PRemium Construction Adhesive, by Loctite, at least along the keel line, followed by the paint after it dries, definitely gets my vote. That will not flake or scrape off, pretty much no matter what you do. It doesn't have any uv protection, hence the need for paint over it.
Try it on a piece of scrap fabric and see.
Just paint works fine, though!