The hull construction became a departure from OOB (out of the box), into scratchbuilding.
I initially glued the below waterline part on, but it looked all wrong.
Following the guidance of the late Prof. Tilley, I have always found drawings of my subjects and made copies at the appropriate scale.
In this case, those of the Atlanta Class by Raven.
Indeed, the submerged depth was shallow by 0.15 inches on the drawing, or a little more than 9 feet at scale and that a lot.
I cut a "plug", in this case a full hull plan footprint, on my little table saw.
It was laminated under the waterline hull part, and the original submerged part was laminated to it.
The stern third or so was incorrect and the result was replacing the sternmost part of that, or cutting it off.
The armor belt on the model was incorrect in several ways. It extended all the way back as cast, to the transom. In fact it only went from the front end of the engineering and control spaces below deck at a line about at the front of the front bridge superstructure, to the rear of the stern engine room.
The model as cast had the belt about 24" thick; it was 3.75" thick.
I relpaced the lower part of the belt with styrene strip on the plug part of the hull. That worked out well. Here are the results so far: