Fitment seemed pretty good - I didn't realize anything was different at first, except for the fact that the speed nuts were clipped to the bottom of the flange because there are no rectangular cutouts in the replacement strip As I stripped away the paint and accumulated crap on the flange, I noticed I was digging into a quarter inch or so of body filler. I was concerned there was more structural damage to the fender from rust or a collision, so I just kept going.
I'm most concerned about the reduced stiffness along the replaced section. Without the stamped indentations in the original, the fender seems more likely to flex along that mounting plane, working the fasteners and the fender itself back and forth. I'm concerned this will lead to gaps (moisture traps), weakened mounting screws and sheet metal, or other problems
For reference, here's what it looked like before I stripped it.
