This is an old thread, but heres a suggestion that works. Go to a sign shop and get a piece of magnetic flexible sign material such as the type that you see stuck on the side of vans. Cut, or have it cut to the appropriate size, and stick it to the bottom side of your louvered hood when it rains. Or leave it there and just remove it for shows. It's flexible so it conforms to the shape of the hood and it's easily installed or removed in seconds.