de,
Mine is mounted high on the rear cap facing rearward. But I like your idea? I think to be most effective "up there", you'd want it to by about a foot higher than the roof at the front cap. Otherwise, mounted low "may" not give you the correct perspective on whether that branch that just passed the camera is really going to take out the AC.
Or do you mean, forward facing mounted on the roof at the front cap? That may be a good option.
I read a while back on RV.net of a guy that ran his camer cable in the seam where the cap meets the roof and down the side where the cap meets the sidewall. He sealed it in with sealant. Guess it beats another roof penetration.
If you end up trying a roof mounted camera, please let us know how it turns out as it sounds really interesting.
Jim