Hey everyone, so my 72 nova came with a set of window felts for the rear quarter windows. The set has 8 pieces but only 4 can be used? Two sets have screw holes, the other two sets have clips. Can you use either set? If not how do I know which set works on my car? My rear interior panels already have the inner felts on them, so I'm just trying to put the felts on the exterior side of the glass. There are two rectangular holes in the metal on the quarter panel, I was assuming the clips went in here? Or do you metal trim screws with the pieces that have screw holes? Thanks in advance!