How do I get a corroded relay pin out of the fuse box? Or do I have to replace the fuse box entirely?

Hello, there is definitely nothing conventional about this, and no procedure that is a known workable fix. If you can find a way to navigate to the terminal side and can get that out of the box, you may have success. My bigger concern is that corrosion of some kind may have caused irreversible damage in general to the box, and will likely need replaced in whole...which I believe is part of the wiring harness. It comes fully assembled from the factory, so it is never meant to be served in the field. Good luck.

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