Jim....I agree, anything you can fix yourself is better than driving to a dealer and waiting all day.
With that said, Newmar uses a staple or brad gun and drives a couple of staples into those grills to hold them in place. You have to pry them off, pulling the staples lose. If you have something thin like a putty knife, place a plastic table mat against the wood, and pry the edges. Once I remove one, I usually use Velcro to reinstall, or you could use silicone, which would make it easily removable later.
Don & Mary
2019 Newmar Dutch Star 4018
2019 Ford Raptor