Yeah possibly mountings for a tow bar maybe, didn't think of that. Strange they would come with the bus but don't fit the bus. That said, the guy i bought it off had stripped 3 separate bays at the same time of various year for restoration and mixed up the bits so
They look like the side plates for the US towbar, its a tubular bar with a swan neck towball mounted to it, towbar unbolts out of the middle and often come available without the end plates as they double as the bumper brackets. If you want to get rid of them let me know as we occasionally get offered the bars.