I have PPF installed on my car, full front bumper, mirrors, and partial hood and fenders. I thought that it is beneficial to install the ceramic coating on the PPF too, but the Crystal serum light instructions say to avoid the PPF. So should I apply it to that or not? If yes, how do I deal with the edge of the PPF that goes across the hood and fender? Do I avoid applying it to the edges of the PPF?