70 340 4spd Bench Seat Question

These are the clips your looking for. I couldn't find them specifically for the seat pivot pin yet, so I can't say that they will be the correct diameter. It was a while ago when I did mine.
When I put my seat backs back on I just put a plastic washer behind the arm so it didn't dig into the fabric. There was never one there when I took it apart, just something I wanted add.

MOPAR Trunk Hinge Retaining Clips All Dodge Chrysler Plymouth W/1/2 Stud Set 2 | eBay

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