I just did it to my van's head lights, they're real big!. They guy that sold them to me said "if you can do wall paper you can do this". Let me tell you, I got them on but they were just a wee bit tougher then hanging wall paper
Just take your time and be relaxed and it can be done, but, its tough going. And thats just the headlights I'm talking about, not the front of the car.