I would use Awlgrip. Sure, it's a marine paint, but it looks as good as a spray job if you use a roll and tip technique. That's right, you can roll on a paint job that's almost as good as a spray job. Throw in a little wet sanding and polishing and it can look as good as a spray job. The best part is, you didn't make a mess of your garage by spraying. Now, the gloss isn't going to be quite as good as an automotive paint, but it's going to be 10x as durable. If luxury yachts are shiny enough for your taste, most of them are painted with Awlgrip, then this may be the right paint system for you. Of course, follow all necessary safety precautions since you are painting in an enclosed space.