Thinking further, you'd still need a new hull for the Long Bin - IIRC the conversions were lengthened quite a bit to fit in the cruise missile launchers.
A Twin Cylinder would be easier to make.
This link here has quite a bit on info, once it's been run through a translator:
http://www.deepstorm.ru/
There's some nice longitudinal sections on a few of the pages.
Mike.
