It was hard to tell from your pictures what your concern is, just a couple of fenders sitting in the bed of your truck. Do you still have your old fenders? If so, match them up flange to flange to your new fenders, right to left and left to right so we can see how far they are off. My glass fenders came without mounting holes so I used the old fenders as a template. It took a bit of coaxing and a few clamps to get them to match up, then I marked the holes for drilling. It also took some force to get them mounted on the bed, but they pulled down tight and look great. Mine came from Old Chicago Street Rods. I can't think of any other old trucks where the rear fenders are close enough to be mistaken for an AD fender.
John