Number Plate Caravan Mount

We have a caravan that could be towed by different vehicles,
we couldnt find a mount that allowed you to change at will,
so until we can find a magnetic solution
I designed and printed these mounts that when attached would allow the numberplate to be slotted in depending who is towing.
It worked perfectly, the only thing would be to slide some paper in behind one side to stop it jumping out, where we mounted though it couldnt jump but paper made it more secure, working on V2 with built in