I don't think you should have any problem with the paint reacting with the plastic of a Fiero.

The paint appears to have no problem with compatibility on plastic bumpers, moldings etc on other cars.

BUT... maybe the smartest thing to do would be to do a test piece. You can probably find some section of a Fiero at the auto wreckers / recyclers. You could do a full out test on that piece and take it to one or two complete sequences of the process.

The only reason I am a little hesitant about giving a 100% thumbs up to going ahead without a test piece is that the type of plastic used in Fiero bodies is a bit of an unknown... Even if you were to test out the process on just one of your own piece. you will be assuring yourself that there won't be any adverse reactions when the mineral spirits and paint start accumulating on the body parts.

I don't recall anyone ever mentioning that Fiero's are handled any differently at body shops then say a starndard car. So I think you will be able to use the process with success... but do a 'test' piece just to assure yourself ( and to help develop your technique )

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