Just for the record, I was unconvinced that it was orange. I was unconvinced that you could tell it was orange from those references, specifically. There are a number of possible variations based on those initial photos, including the one of the boneyard. In black and white it looks like another shade of grey. does that grey mean grey? Or green? It's similar to the center of the hinomaru, so is it bright red? No, surely not. You can interpret a lot from B&W but you cannot tell color. You can't even compare shades and say "it must be between this and that" because it doesn't come out that way in the photo compared to the subject.
My point was: I doubted the orange. One thing lends some logical support to the idea, though:
Skipping the translated caption, the interesting thing is the number codes are white as mentioned. You wouldn't put white on white. Or white on grey, even. Assuming it was some shade of light colored paint it would most likely be black codes.
To me, that logically says a lot more than black and white photos that don't convey true tone or color. Even though you can't tell what color, you can get a piece of the puzzle.
With all the above in mind, I'll admit it's quite possible the tail was orange, as depicted. I wouldn't have thought so without the above photo, though.
