If you're hardcore you can resort to navel jelly, my two outriders needed the navel jelly treatment. Took about two weeks per because the bowl has to be tilted to keep the product on that spot, inside then outside. Be careful because if the rust has worked it's way thru the navel jelly will clean it out then you will have a hole there, had this happen to the second outrider. The end result is rust free and nothing to worry about.
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