It’s a small ship, and all it would need is the main bridge area(of course, inside the ship). I have no modeling/skinning skill whatsoever, and I definitely don’t know how to port, so maybe somebody will take this up.
When I say model, I mean something like the IAC, except the Normandy isn’t as large as it(only about 2/3 as long as the IAC, about the same height).
Pics-
The Ship
http://images.wikia.com/masseffect/images//1/1a/Normandy.jpg
CIC
http://images.wikia.com/masseffect/images//c/cc/NormandyCIC.jpg