Yes, the rings are '56 truck.  Take the headlight buckets out.  Draw a circle in the fender opening around the ring.  Trim the opening to within about an inch of the circle.  Cut radial slits about an inch apart, to within about 1/4" of the circle.  Bend the resulting tabs back to the same angle as the ring.  Install the buckets from the back side.  On the Hurricane I used screws and nuts and spacers to get the headlight positioned where I wanted it in the ring.  On the Ranchero I fabricated metal rings with the forward part matching the angle of the tabs and welded to the buckets.  I put sealer on the mating surfaces and screwed the adaptor rings to the angled tabs.  I drive this truck on the street, and the adaptor rings keep road splash off the wheels from coming out around the headlights and rings.  Hope you can understand this.  Good luck.