John,

The number plate panel on R3 is made of fibreglass. It has an extruded lip all the way round the back, so it looks something like a tea tray when viewed from behind.

The panel is mounted directly to the rear of the car with bolts going through the car's body and through the 'lip' of the licence plate holder.

The over riders have been removed and the hole in each of the bumpers has been covered by a custom aluminium plate. The aluminum covers are separate from the licence plate holder and do not contribute to it staying in place.

I hope this helps.

Andrew