I am getting ready to install a SpoolFool one piece spoiler on my 86 T Type. After drilling the holes in my trunk lid I want to seal them while installing the spoiler so no water leaks in my trunk. Should I use Permatex Clear RTV Silicone for sealing the bolt holes (my original choice) or should I use something like Permatex Ultra Black Gasket Maker? Either way I need a waterproof seal.