The part Mopar Tim and JimMac are referring to is Support 23-64-273 on this page. I have these and it's not the same piece as you have pictured. Note the slots are angled 45*. I'm still trying to figure out where the part you have pictured goes. It was stuck to the inside of the door because I removed all the parts pictured on this page. The guy who beadblasted my doors handed that bracket to me with the doors and had no idea where it was attached.
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