Doesn't look like Wings3D will do it, but I think I figured out how to do it with Anim8or.
{edit} my mistake, I could do it with anim8or if only there was some way to select facets without also selecting all facets behind as well, and if only the point select tool worked.  As it is there's no way in anim8or to select only the facets that need to be flipped, but the flip command is there, mocking me.