Kato's changed teh blue a couple times. The first runs (which I have) it's almost a blue green.
Later runs, they fixed it to be more accurate. I think you should be fine, as the blue in most to P42 I saw daily on the Hiawatha, varied a lot too, depending on where they did a lot of their service time.
Heck, one of them was running with primer grey where the blue is. That was odd.