Help

And I thought those style pushed down and turned to the left.

Don't think the medallion has come off though.
Take a look at the pictures, as I don't see any provision for a center bolt or anything like that.
Actually it looks like it is supposed to just pull off.

http://www.ebay.com/itm/1971-1974-A...Road-Runner-Coronet-Dart-Duster-/252014856687

And here, no center bolt and looks like it pulls off.

http://www.ebay.com/itm/1973-PLYMOU...ash=item2a5ff23317:g:uTwAAOSwpRRWoMCQ&vxp=mtr