Look at the spot welds around the perimeter of the hood skin and the frame. You should be able to tell of someone respot welded the hood skin back on. Also, the AMD hoods did not come with the internal to Mopar parts identifier on the front left corner of the hood, on the short vertical portion. It's not seen when the hood is closed. Also, there is a way to tell for sure if it's an AMD hood in how it mounts to the hood hinges. The AMD hoods will bind the hinges as the angle is wrong where the hinge mounts to the AMD hood.

You could also put a known original trim ring in the hood and see how it fits. It should be an extremely good fit everywhere, especially at the center hood point. The AMD opening for even an original trim ring will not fit as well.

Good luck.