This debate has been raging for many, MANY years and it won't get settled until original Fisher documentation is found (if ever).
While I have a lot of respect for Jerry, William and Charley, I also believe (my opinion only) that the black was semi gloss based on pictures from the
1968 CAMARO DEALER SALES ALBUM. This is clearly a semi gloss finish. However, I don't have the 1967 or 1969 Dealer Sales Album, so I can't say what those pictures show, if anything.
The Camaro wasn't the only car in the model line to use black accents. The Chevelle, Nova and Corvette also used black accents and these are known to be semi gloss. Why would Chevrolet make every car EXCEPT the Camaro semi gloss? Not only that, but just about every US automaker had cars with black accents, and these are all known to be semi gloss. Take a look at any Mustang or Chrysler muscle car from the late 60's, early 70's and you'll see what I mean.
Our own WEB site also states the black was
SEMI GLOSS, but if and when actual paint instructions are found, this won't go away, so paint it whatever amount of gloss you feel comfortable with. Just be aware that if you have your car judged, you'll be wrong no matter what amount of gloss you use!!
Ed