Real 3D limber holes in Fleet Boats? Possible?

[basilio]

After playing so much with the Uboat mission expansion, I went back to the fleet boat and installed these nice skins
http://www.subsim.com/radioroom/showthread.php?t=113835
My question is about the limber holes in the hull.
The Uboat model has "real" 3D holes (you can see through them), while the fleet boats have only a black paint one (well, the skins posted in the above link do a good job to re-create a 3d effect).
So my question is: would it be possible to add "real" limber holes to the Gato, Balao etc. models? Does this require to re-model the entire submarine in 3D?????