The head tube and seat tube lugs are considerably different, mine match the bike Pcampeau posted to a tee. The difference between mine and the frame he posted pics of is that his had forged dropouts and mine are stamped but from what I've read over the past hour or so many of the Carlton's did have stamped DO's. Given that only the main triangle was 531 it wouldn't be all that odd. I'm going to see if there are remnants of decals under the repaint but I'm not optimistic I'll find any.