How did you attach your 3 point retractable seatbelts?

I ordered a set of 3 point retractable seatbelts from Seatbelt planet and it is clear that I either need some additional hardware or fabrication. If you have a set installed can you post a pic of what you did to make them work?

Seatbelt plant sell this item Retractor Mounting Plate & Hardware | SeatbeltPlanet ,but I am not sure that is what I need or if it is even safe for a collision. The pictures are of the actual style seat belts I ordered and how much space I have in between my seats with the original mounting point. Thanks in advance for guidance you can provide.

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