3ds Max :: Removing All Unwanted Polygons And Geometry Before Texture Baking

I'm working to Move Revit architectural files to 3ds Max, there use Vray for ligting and materials, texturebaking everything and moving it into unity. But I’ve run into allot of problems. I manage to get all the stages done, but there is so much “hands on fixing” that it’s not a viable workflow in RL projects.
 
My largest problem is removing all unwanted polygons and geometry before texturebaking. From revit you get a lot of faces that won’t ever be seen, like inside walls, in between there floors ect. For instance if I was doing an interior I would like to be able to quickly remove all unseen polygons and exterior faces that won’t be seen. Otherwise texturebaking is a pain. It will texturebake huge areas that won’t ever be seen making the process long and affecting resolution. Manualy removing all areas that won’t be seen is not an option.