The flange is gone and fender still has it's shape. Don't think the flange retains the shape just a mounting feature mostly. The fender would be matched to the rest of the body contour (tweaked) during assembly as always. But I don't have, nor have ever had, an AD truck. So I will defer these details to others. I was just speaking as to what I see in pics and my sheet metal design experience. Together with body assembling of TF and 6066.

Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn