That's what I did with mine - I used a fine grit sand block and just sanded the rough looking patches up. Also did that with the plenum. Then hit both with clear heat resistant enamel that most all the parts stores sell. I did them when I re-did my valve cover gaskets, and when I was swapping my '86 GT's flat top plenum for the later engraved style.
[This message has been edited by Fiero84Freak (edited 05-31-2014).]