You don't take them off. You just mask around the whole thing and apply the Plastidip over everything. Then you just peel the plastidip off around the letters and it stays on the letters. Really simple and easy to get great results. Watch the video to see how simple it is.
I'm just the opposite. The white letters on the dark grill are too flashy and gaudy for me. And the white letters on the hatch just didn't look right to me with my color. Besides, there is no other white on the entire vehicle. That's why I went the Plastidip route.
So it looks like the dealer put on aftermarket window tint which is applied to the inside of the windows. That's why the rear window defrost looks different from the outside compared to factory tinting.