Tanks scans are from the Japanese books or volumes of the manga. They are normally of a much higher quality than the magazine scans because they are printed on better paper and such. As for the title/cover page of the manga you erase the original text and redraw the image behind it. Sometimes you can make a patch if there is screentone or parts of images that can be duplicated to make it like what would have been there before. Some people prefer to redraw the stuff and then erase the remaining text.