I'm going to agree with TDW here.
Doing the 3d work and related work to get a playable Sub built is pretty much been done before and can be done again.
TDW has given the basic tools to everyone for free. Not perfect but not for lack of putting his time into it! He's done an OUTSTANDING job!!
Will it work in SH5? That's the question. Until a Unit is cloned or created from scratch? We'll never know.
One trick from the SH3 days? Use JSGME to swap files. It may be listed as a type VII in Game Menu, but is a type VII/41 in visual Game. Or some crap like that.
I'm no longer messing with Game files so it's just my thoughts and take those for what you think they are worth.
@gap
How did you rate up there with me?