Goergew, no I haven't unfortunately. I have looked at the vessels being produced for any clues in the changing designs, but got no where with that either unless I'm missing something.
This subject might just have a bearing on a some mysteries.
1) CSS Montgomery - has the outline appearance of a large sidewheel Arkansas. As far as I'm aware John T Shirley was no where near, but did he assist in some way?
2) Why were two of the Bigbee boats side wheelers, why not all four as screw ships?
3) CSS Jackson, a rebuild of a Muscogee type centre wheeler, but where did the Jackson plan spring from, it has no discernible development path unlike every other late war vessels. Charlie Robbins and I quite independently concluded that there was a European influence on this plan. So far we haven't been able to prove it.
4) William Grave's single citadel and John Porter's double citadel "Wilmington" come into the same category. They just appear fully fledged, apparently. The received explanation is that they were from the Board of Construction "Shazam - just like that" . It doesn't happen .