I have a '67 Malibu Sport Coupe that had factory power windows. I'm putting the doors together and there is a plastic "cup" in the steel door panel which acts as a grommet and water shield in the hole where the power window wires go. It's made of white plastic. I'm missing two, one for a single switch and the other is the four switch one for the driver's door. I have looked for these but can't find them anywhere. Corvette restoration places sell a "power window switch shield cup" part number 3824041, but it doesn't look anywhere near the same. Does anyone know where I can buy a couple of these?