Digging around and cleaning some things up, I ran across about 3-4 mags at the bottom of a box. They are genuine USGI M1 carbine mags that have some pretty thick scuzzy rust marks on them. To be honest, they’ve been in my garage for a few years and looks like it may have been where some mice urine got on them. What’s the best way of removing it and getting a bluing or parking back on them?