A job well done, Jean-Marie
The sign probably went up in 1946/1947 as I believe I remember that was Ford's major marketing message as the war ended. While the war was never mentioned, Henry Ford was a bit of a pacifist, I cannot help but think that the thought behind the campaign was something like after 4 years of war you will be able to get a Ford again.
Seems to have worked, Ford sold a lot of cars and trucks in that period.
Bill