The no hanger is a puzzler. Does it appear to have been cut off? The date would seem to coincide with GB being on the Sonolor Lejeune team. And it is the first time I have seen a date on a Carré frame. One thing that kind of jumps out at me is the finish of the stays at the rear drop. They are not finished in that they are not filled in. In line with the frame being a tool? No gussets at the brake bridge. I am guessing we would see a seam on the back side? Typical Carré. The Lejeune I have owned since the early 70s has the same. Maybe this frame was gifted by GB to a friend after the season? That would account for the later components on it. It is kind of crusty, but I would likely have bought it also just because of the initials.