Hi Folks, First time responding to a post with what I hope will be useful info. I'm tearing down a 76 Dart Sport to have stripped and ran into the same issue with removing the rear seat.
This is what I did to remove the rear seat. I placed a long screw driver in between the seat floor mount and the seat wire attached to the bottom of the seat. The seat wire when it is moved/bent upwards will increase in length along its arc allowing it to clear the seat holding mount on the floor. With one hand on the seat, holding the seat down, use the screw driver or implement of your choice to bend the seat wire up. The seat wire will clear the mount tabs and release. Of course your mileage may vary. Hope this helps....Steve
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