On the general topic of EMD noses (and at the risk of straying too far away from SSW921's questions, which still haven't been answered!)...
I've always felt that the TA units that EMD built for the Rock Island in the 1930s should, as 4-axle cab units with a V-16 engine, be counted as somehow in the F-unit family. (My favorite just-so story about the model designation FT -- Preston Cook has a different explanation -- is that it meant "in the same model family as the T, but a Freight version thereof".) But the TA had a long sloped nose, like that on pre-war E-units. So why did EMD, when it designed the FT, shorten the nose? I think the obvious answer would be that (since a freight unit didn't need such visually dramatic styling) it was to shorten the over-all unit length. There would have been, it seems to me, good reasons to keep the freight diesel as short as practicable, both
---structural (make the unit unnecessariiy long and you are in effect installing a lever to multiply transverse forces when going around a curve, with attendant increased risks of derailment and structural damage) and
---operational (even as built, a four-unit FT set was significantly longer than a Big Boy with its tender, and locomotive length is part of train length: an EMD salesman wouldn't want to go to a railroad president and have to say "We've got the best ever heavy freight locomotive... but you're going to have to lengthen all your passing sidings to use it).
(But that's tangential to the main point of the string.)