Well what I did was take two photos like this (high quality) Of the car with the hood closed and the hood open. I procceded to stand on a latter untill I was high enough where I could get most of the car. Then I aimed the camera at the middle of the hood, best I could.
I then straightened them out Closed hood on the left, and closed on the right. I took the largest blurred clone brush I could use, for instance I think I used 300. And I made sure they were pretty closly centered. I set the clone stamp directly in the middle of the air-filter cover, then stamped on the picture with the hood closed. Basicly I kept trying each time, untill it was almost perfectly lined up. (By staring at your engine for a long time, you know where everything is and should be)
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