Well there is this company that came out with Mikados in Z scale. (You might have seen them advertised in the last few Model Railroader Magazine)
Of course they made some kind of generic light and heavy USRA Mikes and slapped on some paint for the different roads. And of course they will not be 100 percent accurate models of CB&Q engines,
I dont know where they got the pictures for placing the heralds, but all of them (practically every road) placed them WAY aft of the center-line. There was much gnashing of teeth on the forums, and people started to go into one camp or the other, saying that the photos (taken at angles) prove it was so or not so, even bringing in all kinds of math and computer programs to prove it.
Well one of the big wheels at the company who makes them was kind of bragging about how accurate his models were, and they always used plans. That is when I slapped down the link to the painting guide, from the Q, that shows the herald is supposed to be centered on the tenders.
So now we get the "well the guys in the paint shop doesn´t always follow orders" excuse.
Now I know there is nobody here who were railroaders in 1927, however, the impression I get is, that orders for things like painting a locomotive, especially in those days, would have been followed to a "T".