[Mg-t] Re TD Front Brake Backing Plates

[gunnellj tds.net]

What differentiates on front brake backing plate form the other? They have
separarte part numbers

On my car

The backing plate on the left is stamped 4/2RH

The backing plate on the right is stamped 25905/_H

I see these plates have different LH and RH part numbers in the Moss
Catalog, but they look identical to me.

 I realize there is an extra little hole on one side that must either face
forward or rearward (who knows the right direction for sure?),  but it
seems as if you could just flip one over to get that orientation.

Is there really a difference I am missing here?