Probably debris around the resistors in front, they get hot enough to start a fire. I would pull the blower motor out the front, as well as the resistors. The resistors are just a flat diamond shape plate visible in the spare tire area held in by I believe one screw.
With the plate and blower motor out you should be able to pull any debris out of there.
"If any car is both the parade and the rain, it is the Fiero"
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