Not to be judgemental, but I think you missed the fact that Humvees come in many variants, the slanted being just one of them. I'm surprised that you made one and didn't find that out.
Quoting Garetos Wielder of Weapons (mocman moc)
Hey that is spactacular! Hey,I recently made a minifigure scale humvee that I have not posted yet.Not to be judgemental, but I think you forgot ihe slant at the rear.