Did a little more research on your fuse box. In 1975 and 1976 Chrysler added the swing down bracket to try and make it easier to access the fuses.
They used a metal thumb scerw that you would unscrew about one full turn to swivel the box down. A plastic nut was attached to the back side of the bracket. The thumb screw can be seen in the Mcmaster catalog. Go to their catalog and search for: steel spade head thumb screw. Size is 1/4-20 thread size - 1/2 inch long.
