I had these bolts grouped with my stub-frame bolts but I see they can't be for the stub (or at least mounting the stub to the body). I'm drawing a blank on anything else using 1/2 inch bolts except maybe the bumper bracket to stub bolts, I've looked through the '67 Dodge manual but can find no exploded view of bumper mounting. These are the only bolts I've come across with serrated washers, and they also have lock washers (again, very rare). They're about 2 or 2.5 inches long.
![508.jpg 508.jpg](https://www.forcbodiesonly.com/mopar-forum/attachments/508-jpg.674510/)