Do a google search for por-15. I used it on an small area that I had and have had no problems. They guarantee that it will stop rust forever. Mine sounds as if it was in the same spot yours is. I removed the passanger door and fixed it the right way, because usually with rust once you start scraping it away you find that it is a bigger problem that what you thought. It also gave me a chance to replace the door pins and bushings. Let me know if you need and advice/help. Good luck