First, remember that rust never sleeps, and primer doesn't seal. Anything that you have primed with rattlecan primer will begin to rust within a week, depending on your climate. Always paint over the primer to seal the air holes.
Duplicolor is now owned by Krylon. You can get info through their website, and they do sell a clear coat sealer. I have a truck that has a Maaco paint job, the key is in surface prep. If you are able to do the prep, you will get a halfway decent paint job. Mine will probably need repainted in three years, the way it looks. It has no clear coat, the first thing I had to do was replace the leaky gas cap and repaint the side of the truck where the gas ate through the paint. That's how I learned there was no clear coat, gas won't eat through it that fast.
On the rust you can't repair now, I would clean it the best I could, and apply POR-15, it will at least stop the rust from getting worse.
Remember, rust never sleeps. [img]
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