That partictular piece is the nut for two 1/4” bolts on top and another for the two on the bottom. The plate(s) with the serrations is sandwiched between the striker plate and the “B” pillar.

One of our members “KCmongo” has a business that specializes in AD parts. He may be able to hook you up. He’s located in KC but he ships.

Here is his contact info: (816) 265-1462

https://mongosgarage.com/

Last edited by Phak1; 01/30/2026 10:54 PM. Reason: Added info

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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