I wanted to do that with my Serenity when I got it, it was CHERRY! Sadly I didn't and relied on the bug shield on the nose, thinking I'd likely be fine. Now I have lots of chips (also lost the windshield so some pretty gnarly roads) and am thinking about hitting up the body shop and then doing paint protection. I did try this stuff from 3M that sprays on and dries to a film that is like the pre-cut stuff, but it exactly molds to your car. I didn't wanna put it anywhere that it might go bad and ruin the appeal of the RV so I put it under the solar panels I was installing. First I waxed the surface and then taped off any area I didn't wanna get sprayed.
The spray itself was childs play but then the mistakes started happening. I wanted to do the other side for the other panel and didn't wanna sit on a ladder in the street so I STUPIDLY drove the RV to the end of the block and turned around, but when I got on the roof I discovered the newspaper had blown into the sprayed area and was permanently attached. I did not make that mistake on the other side.
The can said to not spray in direct sunlight or some temp so I did it in the evening, but then I noticed it said not to let it get wet for 48 hours... So that means no rain right? Just a few hours later the RV was already covered with dew and by dawn the paint protection was all white and dripping down the side of the RV. It took 4 days before it would survive in the night without changing color. The drips did peal off easily and the remaining taped off area did get a plastic film, with newspaper and dirt in it. If I was to do the hood I think I would pull the nose into the garage first, maybe hang shower curtains to keep the spray dry, but I just went to the local auto parts store and got a can, really easy... Likely easier to do that maintenance on than the one piece film is.
-Randy