I would like to know also. I would guess they changed the cans and boxes at the same time. I have been collecting Firestone catalogs to try and help figure it out. I am missing 55, 56 and 57. In the 54 catalog they are orange and blue, in the 58 catalog they are red and white.
This is my one and only piece , It is double sided with both sides being in wonderful condition. Got it from a ford dealership that had it hanging since new and it came new with Ford mounted in the frame.