Jon, to me, that looks like it has spent many a year in an album, dont see much wear at all, typical mushy strike, but the coloring on the reverse hints of MS-70, whenever you see blue you have to consider that. A proof with that bluish tone sometimes comes from the storage method, but a reg circulation coin like that, I tend to not trust the color
Pretty hard to tell by the pics, but I'll say AU. Not sure about cleaning, or not. The coin looks more and more different though each time you post new pics, lol? Nice coin, and nice strike for a 20-S IMHO. Phoenix