Installed a TV mounting bracket in the bedroom of my Eagle a couple of weeks ago. Don't believe the sticker!
Use a stud finder, instead. I drilled two holes within the sticker and still couldn't find the backer. Finally went home & got the stud finder. Found out the backer was a good 2" below the top of the sticker. But it's about 18" square. That's good, because I ended up not liking the spot I mounted it, so will end up moving it. I originally centered it between the edge of the open sliding bedroom door and the corner (I'm sort of a symmetry freak). Then I realized that the mount has a single articulating arm, with swivels on both ends, and I wouldn't be able to tie the tv to the wall during travel. It would either hit the sliding door, or hit the outside wall of the trailer. So, I'm going to be moving it closer to the slider. Will have to get out the spackle and paint to match the wall covering as well as I can.
Hope you have a little better luck!