Dear Bob,
Prep work is 90% of the job. Sand, degrease, prime, and paint. If the surface is oily before you sand, degrease first, sand, and then degrease again. The other 10% is the paint, and painting.
For areas that have rusted, I have had good luck with rust converting solutions that put down a layer of black iron phosphate/oxide. Paint adheres really well, and the rust doesn't recur easily.
I have always been happier with brush on paint, and two part paint finishes, when compared to spray paint. Spray paint in a can is never going to be a great finish, but you probably don't want to go to the effort of mixing up a two part paint, painting it on, and dealing with the leftover, paint which will congeal pretty quickly. If you do, there are lots of great polyurethane, and epoxy paints out there. Local autobody shops will usually mix you up a pint or two fairly cheaply, but it will be 3-20X the price of spray paint.
Personally, I just try to keep the rust at bay on working machines. Funnily enough, I'll touch up the smallest scratch on a car. It isn't entirely logical, but there it is.
All the best,
Peter
I spray painted my PT with some JD matching green. I did little prep work and it is not holding up everywhere. Any suggestion on cleaning solvents, sanding, etc.
Things were kinda slow on this site, so I thought this might liven things up.
Bob Rip