How to Change a CAS Item's Anchor Point

I'm not exactly sure how to word this, but I wanted to know how to change CAS item's anchor point? For example; I downloaded Maysims' lovely wing mod, however I noticed in game that the wing's movement were not actually attached to the back, they were instead attached to the mouth/jaw - so whenever the sim talks or moves their mouth, the wings jump up and down with it. Since the wings are 'anchored' to the sims face, whenever they look up, the wings goes straight through their chest. It's really agitating, I would like to fix this but I'm not entirely sure how. I'm not sure if this is a weight problem or not.