Many DIY put OC703 beneath the wells of a QRD. Questions: 1. Should the OC703 be faced with FRK or unfaced? 2. Could one use Armstrong 403a acoustic ceiling panels (made of OC701 or OC703) faced with a white plastic instead of the OC703 and use the white plastic instead of FRK if your answer to #1 was that it should be faced with FRK.