On my 2003 X, I needed to be able to still fit the vehicle in the garage as well as avoid hazards like tree branches and brush. Because it's strictly a field rig, it sees a lot of narrow roads with trees and sagebrush. I also don't like to compromise my antenna too much.
I decided to mount a Larsen NMO2/70B on a Diamond K400 trunk lip mount on the hood opposite the factory FM antenna. The mount is such that the antenna is inboard of the edge of the rig quite a ways, and does not need adjustment or removal to pop the hood. I never touch it. The radio is a Kenwood D710A. I mounted the radio under the passenger seat along with a 4005H. The head is mounted on the top of the dash, center. The mic is run through the center console and lives there when not in use. Wiring is clean and nothing is visible.
After 2 years, the antenna has proved to not be in a compromised location at all - I am often quite a long ways from the repeaters that I use and do not have problems getting back into the machines. The mount and antenna have held up just fine, and nothing has come loose (I used blue Locktite on the set screws for the mount). I also ran a plastic sheath (split clear tubing) on the K400 coax from the mount back through the firewall just to protect it.
All in all, I can't think of a better 2/440 setup on the X than this one, and I'd do it again exactly as engineered the first time.