Duster/Demon rear seats vs Dart/Valiant ?? Interchange??

I put the front and rear bench seats out of a 74 Swinger into a 74 Duster. The back of the back seat fit perfect. The bottom of the back seat was very hard to get latched down to the floor hooks, but I finally got it. The bottom of the seat looked like it was made for the Duster once I got it in place.