That makes sense. Also has the small hook eyebolt for a safety chain or to attach a cable to the pin for the hole? Could be it.
Was this another former Wackenhut Security/Nevada Test Site Security Car? With the rear wheels mounted on the car, would there be space on each side for a spare centered where each of the receiver mounts were?
And in the movie "(The) Delta Force" were there spare tires or something else mounted in that B Pillar area on the FAV they used?
One of the Nevada, AZ or NM area FAV has racing seats mounted in that B Pillar area.
The 9th ID Korea "Team Spirit" deployment XM1041 TOW FAV have a 5gal military fuel can mounted in that area. Or it is that NBC Decontaimination device that looks like a 5 gallon MFC, and I see an NBC M-11 Decontamination Device hanging off the strap holding the MFC/Decon Device :
This device, I can't remember when this was adopted, I was trained on the smaller nitrogen cartridge powered M-11 fire extinguisher looking device you see on the above FAV.
9th ID was the high tech test bed unit, they could have been field testing the M13 during the Team Spirit deployment
Plus the XM1041 TOW FAV has that unique almost U shaped cargo bin around the engine bay so the Gunner can sit in the center.