Here are two of my many cases where no visible paint was left when i got them, and here is the after of each where I was able to bring back the original paint to some degree with just elbow grease and time. Neither have had paint added and neither have been polished, just scrubbed and cleaned.
What looks like "solid rust" in most cases is just millions of little rust dots and covered in rust staining from rain and run-off. You would be shocked at what can come back
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