part sheets can be found here http://shipbucket.com/images.php?dir=Parts%20Sheets
and in the parts sheet section of the forums.
no worries about the crediting, this is actually in the grey area if crediting would be needed.
as for the torpedo tubes: the tubes have to be reloaded, and for that there has to be an room somewhere behind those 2 hatches that you see. even if the actual opening is completely watertight, there is still an odd deck level there. in addition, you always try to keep openings in the hull below the main deck to an minimum, because those are structural weaknesses.