73' 340/904 duster racestoration

That striker looks like a bad attempt at repairing a common a-body issue, those strikers break free pretty regularly. My Dart has the same issue, minus the poor repair. Here's a link i was given to do the repair right: http://www.moparmusclemagazine.com/...0101_repairing_a_body_door_striker/index.html

Good luck with your project!