In the USA, the blue 235 was a color only used in cars.
I think that Tonawanda, NY and Flint, MI were the two engine plants in the USA?
My opinion, which cannot easily be proved or disproved, is that the shade of gray for truck engines changed when the 235 changed from low-pressure to high-pressure (in 1954).
Blue gray truck 235s from 1960 onwards were reported in that VCCA member's article on paint colors, and a green 235 in 1957 was reported.
I have seen nothing about Canadian 235s, except they usually spell gray/grey differently from us southerners.
