Now some of this Information may seem... "Navyfield esk," and yes.. I play it alot. Still.
However, there is truth in it as well.
The Conqueror was arguably planned as a Lion 2 design upgraded. (Temeraire was one of the Lion 1's etc). The Lion 2 design however, had 18" Tripples. Although much of the documentation around that is... bleek.
Or is this on the other weird Battleship project that I forgot the name of, but was similar?