Tony,
Great info in your posts. The photo of the C&NW(Roary #13)
has the side layout that seems close to OM/ON. The raised
roof above the front door(visible after the 1908 rebuild) and the front windows appear bigger than on the few views of OM before the rebuild
I´ve been able to find. I´ll try a rough layout using the lower side
profile and add the doors annd windows to see what I can come up
with. I tried manipulating color, brightness, and contrast to identify the front service door location with no sucess, I suspect that OM
had only one service door that started below the front window
and extended to just in front of the next window along the side
giving acess to the cylinders.
Thx.
MCG de Oliveira