Hi
From what I remember, the 3609 was a more standard RS-11 than the other CV/DW&P units. They were early RS-11s with the lightweight MLW trucks (in later years anyway), and the earlier style shorthood mounted dynamic brakes. The former N&W unit was added as a wreck replacement and had a more usual configuration apart from the odd (N&W style) car body filter covers. All were short hood forward. I believe it was this unit that went to the Maine Coast.
I'm not sure about the "m" classification of this unit but externally it was largely standard.
Cheers
Steve
Modelling the M&E in NZ.
There's only one Alco in NZ. 8-(