Of course you have to have the OBJ files with the alternate UV maps to do this. That was easy to create. So here's the first designs for the narrow/rectangular shields UV swapped:
I'm now trying to remember how to put the alternate UV mapping into the Poser files... cue question on the Renderosity Poser forum.
(P.S. inspiration for this came from a render by luckybears at Renderosity)