Hi guys. On view port locations.....although my hull is a little different than most, I've found that doing full scale mock ups of the sub has helped me a lot. Not only for window locations, but even way back before I decided on the hull shape. I made a wire frame and covered it with card board. It was very cost effective ( almost free ) and really made it clear where to put the windows. I've made several of these now, and use them for locating the battery banks, approximate seat location and size, and sometimes just to sit in there and
think. This has saved me some very expensive mistakes. I highly recommend this approach. Frank D.