Thanks William,
Know this pic well. Some engines acquired from other roads got the "Rio Grande look" quite quickly like #431 (361) While others, such as a shot I have seen of a C-18 as a #400 series engine (pre 1924)iook much as they did on the prior road. The C-18 looks almost catalog Baldwin. As the Crystal River #103, old #375 would almost qualify as a mother Hubbard type. The backhead is out in the air, like the Pomona engine (a sister to #375) and WP and Y #69. Crystal River built the big cab according to one caption.
Just wondered if there was any pre 1924 info on the engine floating around out there. I sure as heck have not seen any. I'll search a bit more, perhaps CRRM and De Golyer. after that, I guess I'll just do the model as conjecture ie: the way I think looks neat!