Bob,
I have a bunch of photos of the USS Lionfish, I could send you a couple if you think it would help. Also you can find conversion resin kits for this model at
www.nautilusmodels.com . I have the kit as well, there are more than a few things wrong. The deck gun being one of them.
Here is another site you may find useful,
http://www.shipcamouflage.com/submarines.htm
Take care.
Don