I signed up just to comment on this thread. I just purchased a 2015 Mustang GT convertible and the body panel fitment is horrendous. I haven't bought a new car in a long time and I've never spent this much money on one and I am not happy!
1.The bottom rear of the drivers door sticks out at the bottom. Not even close to matching the curve on the passenger side drivers door.
2. The rear edge of the trunk is not straight. The gap gets wider from right to left and increases greatly on the last inch or so.
3. There is a defect in the paint bellow the driver side mirror.
4. The rear bottom spoiler does not line up with the fender. I actually believe a clip is broke or missing.
I've owned the car for one month and I will be taking it back to the dealer when I get a chance, but I know from past experience with dealers and manufacture representatives, that I am screwed. Other than the clip on the rear spoiler, I will send emails, make phone calls, waste a lot of my time and nothing will happen.
I will follow up with pictures when I get home.