seen different style screws offered from different vendors. pan head or a flatter style phillips. also are the ones used in the btm corners use a washer or just a flanged nut? are the amk produced ones dead on? are all screws mounted prior to paint or just a couple for a 70 gt500 june/69 . i suppose valance was removed to chop out the exh hole or was valance replaced with a pre cut one at kar- kraft ? thanks