74 Duster bench to bucket ???

In your last pic, those are 74 Duster Buckets. They will fit in a bench car, but there are two extra holes that you will need to drill for the two inside studs. There are a total of eight holes for cars w/buckets , but only four for a bench seat. The two inside holes on each side came from the factory with a thin piece of metal welded on top of the floor where your inside holes are, for support