Dave,
Prototype photos I have show no surface treatment on the walkways.
Look closely at the Santa Fe photo, the handrail bases should be parallel to the hoods.
...and no seam around the cab roof.
...no seam near the hood ends.
...no oversize headlight.
Hood ends are not as steep, are a bit more rounded with little to no walkway area at the base.
(Note the extra doors on the hoods and skirt, spark arrestors or mufflers on the stacks...unique to the SF?)
Too bad Williams/Bachmann failed to make the effort to review published drawings and photos but instead copied the RY model...would have made more sense to copy the Smoky Mountain Model Works 44 ton S scale model...the most accurate to date.
It would be refreshing to see MTH put forth the effort...and provide a 2-rail conversion. 
Thanks for the comparison. I wish MTH had done a 2R unit…I would have just waited for it, but alas they did what they did. I'll just 2R the Williams despite all of the flaws you have pointed out. If the hood-width is so very wrong, I can live with the rest of the problems. I guess both companies thought RY satisfied the 2R market for these and that it wasn't worth the cost. Oh well.
If MTH's unit comes out and its easy to 2R in the end, maybe I'll pick up another one.
