Rear Seat dimensions and bracket pictures

[Stang Guy]

So we recently purchased a 72 suburban that came with 3 rows of seats. The middle seat was installed and the 3rd row seat is not and does not have brackets on it. The 2nd row seat is shorter than the one that is in the back(3rd row?), and the one in the back is wider than the wheel wells.

So couple of questions. What are the dimensions approximately of the middle and 3rd row seats? Are they the same or is one longer?

I believe the 3rd row seat should have around a 4 inch bracket. Does anyone have any pics of brackets they have fabricated? Or is there a place to buy them from?

All the seats have the same upholstery so I'm thinking they are out of the same vehicles and look like suburban seats from the 67-72 time frame.

Thanks for the help.