And one of the major modifications, which was to add almost a 1/2 inch of reinforcement material (urethane bumper repair material) to the outer edges. Due to bad molding of these parts at the factory, the outer edges were at best, 1/64 of an inch thick and brittle as glass. The polyethylene valance was a great visual design but very poorly executed. That was why the vast majority were replaced by the visually different, stamped steel valance under a blanket warranty/service bulletin.
The other major modification was to fill all of the existing mounting holes and then redrill them in the correct locations so they would actually line up with the factory mounting positions on the radiator support. Some of the holes in the valance were over an inch away from their mounting points. The assembly line gorillas didn't care, so they would just shove the valance into place and make the bolts hold it there, til the car rolled to the end of the assembly line and the valance shattered once the car hit the first bump - usually the ramp onto the delivery truck.