I have something that goes through my tubing and it acts like the same thing in my 65 light blue dodge. All it does is keeps the seat stiff but it is not good for side to side movement.
I had a long talk with my chassis shop and what we did in my 65 Plymouth was to weld a tab from the rollcage to the back of the seat and bolt it in to the seat so if a side impact or roll over the seat is going to fly around.
Going to do the same to my 65 light blue dodge next time it goes to the shop.
So that is an expensive, glorified seat stop.IMO
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