I think all the floors are the same and all seats snap in and out. My 8 pass is config like this:
2 part wide bench seat holding 3 people in rear. It takes up the full width of the van and those two parts can only be mounted in the rear.
3 part bench seat in the middle row (like others have mentioned) holding 3 people. It takes up the full width of the van and right seat can be mounted in right rear. (left or center) can be mounted in left rear.