David,
I personally think it is a false hope if you have not casually turned it up by now to find what you wish for on these two locomotives. They are such well known icons that if such complete drawings existed, it would be known by now.
I disagree that if the locomotive is larger that you need more drawings, particularly if the prototypes still exist. Seeing as they do exist, you need to develop relationships with the owners to give you access so you can field measure the parts that you need.
Even if you could get the Baldwin drawings for the K-27, unless you want to build a slope back tender Vauclain coumpound 2-8-2, you will again be out of luck.
I think your best bet for the K-27 is to get a hold of one of the copies of the Baldwin Locomotive Works Standard Practice that were briefly reprinted by Little River Locomotive Co. (yes I know it is updated to post 1945, but it is still very valid);even though they are gone, I got my first copy from a railroad musem CMO ten years before the reprint, so they are out there. I have dabbled in a possible 7 1/2" gage Baldwin trench 2-6-2T using this resource; but I have to warn you, I have the original Baldwin side elevation of this locomotive and it is not correct to photos and other documentation, either.
(If anyone has the cross sections for this locomotive, please PM me!)
Even in 1/4 size old "square cube" is going to get you; the boiler cannot be a 100% scale model and be sucessful; and some other items will still need to be re-engineered to sucessfully operate at 1/4 size of the original.
Existing drawings, field work, and the standard practice would allow you to engineer something that would be so close that only you would know what compromises needed to be made. As the late great Walter P. Gray said, you research the object to the extent possible, and then you make coin flips. It is done all of the time in historical restoration and reconstruction.
Steve Zuiderveen
