Jim
Getting the tenders behind the correct locomotives reminds me of one of "Uncle Bob's" many stories.
One of the brass model locomotive importers spent quite a bit of time, and many rolls of Kodak film, measuring and documenting engine number 346. Bob would tell the story of all the dedicated work around and about 346. And then Bob would solemnly relate, with a twinkle in his eye, that he just did not have the heart to tell them that the tender they carefully measured and photographed was the one that belonged behind number 318.
So, there may not be a terrible great amount of difference, but my HOn3 model of D&RGW class C19 346 has a class C18 tender on the drawbar - Ulcle Bob said so!