For top loaders: If you don’t have enough clearance for the 1/32” NDM between the data side of the CD and the transport surface above which the disc is spinning there’s something wrong with your CD player. Furthermore, even if there isn’t enough clearance, which I doubt, the NDM will be effective ANYWHERE inside the CD transport compartment since the scattered light is filling up the entire space inside the compartment, lighting it up like a Christmas tree. NDM is not limited to the gap between the disc and the transport.