I do not want to damage the yellow paint on this shell. The rust is thick in some places, hopefully not deeply pitted under the rust. Hazord recommends Evaporust, I found it at O'Reilleys auto store, $10. I jumped right in and followed directions. I painted the liquid on, wrapped in a rag, used magnets to hold it in place, poured in more liquid and placed it in a plastic bag. I will unwrap and check it every 6 hours or so. See first pictures. First thoughts, this stuff is water thin, I will have to turn the bag to distribute the liquid. I washed my hands in it to check if it is harmful, no adverse reactions...day one.