So, Im cleaning up my old 'spaceliner' (Murry 'M.O.' stamped) steel rims (complete wheels); I have to wire brush the inevitable rusty spots on the tube liner side and am thinking that some kid of paint might be a good idea in there. What do you guys recommend ? Id like it to be good for another 40+ years. BTW, the SOS pads did a great job in the outside surfaces.