I have one. It says "Macintosh II" on the front, has a IIfx board and an injection molded plastic plate that says "Macintosh IIfx" with the corresponding model number, copyright and FCC info, etc. stuck over the place where the original bottom tub molding says "Macintosh II" and the rest of it. Just like Concorde1993 describes.
Mine also has a Microsoft property tag on it. But that's another story.