Hello Kevin,
Excellent model of the Nashville, it captures her unique appearance and unusual paddlewheel boxes. As you've mentioned above there are a number of sketches that don't always agree with each other. The inconsistencies could be due to the artist's view of the ship (from a distance), or from the time of the sketch (while being outfitted vs. as commissioned, etc.). I have seen one sketch depict a smaller pilot house just aft of the forward shield while another depicts it as an extension of the shield and much larger. Both could be correct as they may depict the vessel at different times.
One of the great rumors in the CSN community is that her plans were part of the Warner collection at the CWNM in Columbus. They were given as part of the original donation back in the early 1960s but have long vanished. Whether a collector or researcher ran off with them or they were misplaced and destroyed, no one seems to know. This is akin to the son of the Eastport's primary contractor offering the drawings of her CSN conversion to the Tennessee Historical Society in 1923 and they have no record of receiving them. One can muse all day about what has been lost from this conflict as well as more recent ones.
Anyway, besides the known sketches, there is a photograph that shows a very limited view of the Nashville postwar in New Orleans. Only her funnel, uppermost casemate, hog braces, and paddleboxes can be discerned. But it does add to our limited knowledge of the vessel. The hog braces were placed at an angle and the chains appear to run across the beam, not longitudinal, and attach at each end of the paddle boxes. This makes sense as her hull beam was 62', and overall width across the paddle box's armored sponsons was around 95'. It would require transverse hog brace & chain support to properly suspend those heavy sponsons on either beam. That width with her length would give her an almost 3:1 length to beam ratio and certainly contribute to her appearance as a 'monster' of an ironclad.
While no plans are known to currently exist a schematic diagram of her gundeck, with measures was submitted for approval when planning her armament. Of interest one can always identify her ends from any perspective using the following details: the forward shield had two gunports and aft shield only one gunport. The two broadside gunports ahead of the wheel were spaced 17'6" apart. The broadside gunports aft of the wheel were spaced 13'5" apart. In addition, the forward shield was 31'5" wide and the aft shield 27' wide (all from NA-1091 reel 10, plate 747). I do believe her funnel was aft of the wheels and of course, boats would have been mounted aft.
I do enjoy your work, please continue to post your projects.
All the best,
Bil