I had a pair of 05 seats, and the way the track is makes it impossible to simply drop them in. You have to make some sort of bracket that will make it possible to bolt them into a fox.
I know that Ford changed the seat frame in either 2007, or 2008. I saw the seat bottom of those, and it look much easier to fab something up to those tracks than the 05's. That would be my suggestion getting those 08 seats vs. the 05's.