Most any Fiero will be afflicted by this, if it's been in the sun long enough.
I've thought about epoxying a thin, flat piece of... something to the inside of the fascia, There is obviously a bit of space (guessing maybe 1/4 to 1.2 inch?) between the top of the eggcrate and the underside of the fascia.
Also, you can restore the normal shape of urethane bumper covers with a heat gun or even a hair dryer.
The fascia that I installed on our black Miata was deformed so badly from an accident that the guy gave it to me with some other parts I was buying from him. (He was parting the car out, as a result of that accident.) Less than an hour of work with a hairdryer restored it to normal shape.
(The "damage" was on the driver's side. You can see a couple of scratches above and below the parking light. Was not even bad enough to have it repainted.)
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