The Railing SW1500 assuredly does have a correct scale width hood (6 ft). The prototype's hood is 12 ft 6 ⅝ inches tall from the railhead. The model's hood scales 12ft 10 inches tall from the railhead so just 3 ⅜ inches off. The height of the prototype's hood from the walkway is 7 ft 2 inches and that of the model is 7 ft 5 inches so again, just 3 [scale] inches off. 3 scale inches at 1:48 = 1/16 inch (actual). Close enough to scale dimensions for my 70yr old eyes. 
The MTH PS3 SW1500 is my favorite model locomotive.
Incidentally, the prototype EMD NW2 had a 7 ft width hood as did all EMD end-cab switchers until the release of the SW1500. The iconic Lionel NW2 has a hood width of (scale) 7 ft 8 inches.
