Can I use normal / generic spray paint on the undercarriage of my TJ?

It lays down even with a roller but dries with a slight texture to it. It isn't easy to photograph but here it is on flat steel. The frame sections I rolled had enough damage due to surface rust that was much more pronounced than the texture of the paint if that makes sense. The large flat sections on the skid are totally even with this slight texture to them. If you brush it on it will have streaks. I was going to thin and spray it with a gun but for some reason I got the idea to roll it.

skid-paint.jpg