if those inside faces are connected to the outside faces then technically they are all part of the same continuous shell. only way i can think of is if you are using maya, try selecting with "camera based selection" checked. this will only select faces that you can see from the outside. then you can just invert selection…
http://screencast.com/t/Jvm8MUGnLU I want to be able to select only the faces that are inside a continous shell like this. any scripts or methods you guys can help me with? Thanks so much for any hints