I told you what it was for in my first reply.
in velles/minibuses etc that have a full width rear seat , well this seat can fold flat and to locate it there is a pin on either siide , this pin screws into the bracket you show, and on the seat there is a catch ,, foillow
an one time your van was a multi seat peolple shifter....
brikyard amongst others sell a mounting plate that is up to the job , search wiki for info,on fitting, best way is to drill a good clearance hole for the belt bolt and say 4 x 5/16" holes and locate plate behind panal and puddle weld through, strongest way to do it , welds meely hold the plate in place as the fact that they are behind the panal gives them all the security they need
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