I am planing on 3-point shoulder belt for the driver and passanger but only 2-point belt in the middle. So i needed 4 mounting points in the middle, 1 for each 3-point belt and 2 for the 2-point belt. But I also wanted to save as much space as possible, so I figured this configuration would keep the strength according to the seat belt suppliers recomendations but minimize the distance between the mounting points. The belt mounting will be on each side if the brakets but on the same bolt.
Keeping everything anchored with a big, thick stainless plate on the underside.