Correct. The orc models are not dynamic (i.e. don't show clothing and even some weapons when equipped) so you would need to change to a model which does support those things.
It's important to note, however, that regardless of which model you might have, it doesn't really disguise the fact that your orc is an orc (i.e. size, shape and face) and that he still will not be permitted in Port Hempstead (and possibly other towns, depending). Clothing, however clever, will also not disguise this, and there are IC consequences for being in places that disallow monstrous races.
