My first car had the mirror mounted on the fender, as outlined in the manual. That mirror/location is pretty much useless. I was able to improve it by using a parabolic mirror instead of the flat one in the housing. (Be careful, it needs to be the long-range 'flatter' style, not the style typically used on the passenger side). In the end, it was passable but not good. Plus you have a couple holes in the body that can't be easily patched if you don't like it.
On my second car, I mounted a Raydot style on the windshield frame. Much better but you get an edge of the side vent in the mirror image. But at least you can see a car coming around the side of you. I did have to drill and tap the side frame for the mount.
