The top edge of that quarter is supposed to be bend up. To pull it down with clamps and weld it makes it more rigid. A panel without surface tension is called a blooper because it makes that sound when it moves in and out. I hope that makes sense.
There are no dents or dings in my AMD sheetmetal. They are properly packaged to prevent that. I have full 1/4s and roofskins to prove that.
We in the body world call that "Oil canning". I really don't think you need tension in the replacement pieces.
All other inferior replacement panels were stamped to fit "Over" the original panel. AMD is a OE style 1/4 that is a direct replacement. No jacking around with fit for sure!
All my sheetmetal needs are filled by AMD whatever the car may be!