[krausewich]

Nice advice above. I would not recommend going as low as 180 grit though. Even 220 may be a bit much. A fresh piece of 400 will do a great job for a bit. Work your corrosion areas lightly with the paper on a sanding block to remove it the best you can. work the AREA, not just the spot, otherwise you will end up with noticeable dimple in the panel. Then follow up with passes over the worked area to rough blend the grain, then full panel passes with fresh paper, and or scotchbrite to blend everything. OR hit the whole thing with some 800, then polish it up : ) Good luck !!