If you go to the other thread you see it is a redial so that is of little help. I am not sure when GP would have switched from 15 to 17 jewels for it's winders but I suspect they were an early adopter. If so, I would place it in the early 40's. Maybe someone will be able to recognize the bridges and place the movement.Thanks for posting. Just looking at the movement, I'd place your watch in the late 1940s.