I was playing around with different GoPro mounting locations the other day using a Hero 3+ Black, a Hero 3 Black and a Hero 2. I didn't take any pics of the mounted cameras unfortunately, but the Hero 3+ Black was facing rearwards with an open back door, suction cup mount right beside the license plate. 1080p/60. The Hero 3 was facing forward with open back door with foam inside the door, 1080p/30 suction cupped to the front right fender on the top of it. The Hero 2 was mounted on a roll bar mount off my harness bar in the car, set to 720p/60.
A quick video I put together with the clips: