Thanks, Bob!
The CJ hood scoop was a separate item, that attached with 4 (or 6) studs that were attached into the hood underside. Holes were drilled into the hood, and the scoop just sat on top. Nuts with washers held it on the underside. (right, Bob??).
I've never seen that hood scoop as an "official" type of dealer option in '68. Some catalogs for the Ford Performance, and Shelby had it for '69 Mustangs, and as an add-on for '67 and 68 Mustangs.
If you want it on your GT/CS for looks--then go for it, but if you show the car, you'll have a hard time "justifying" it to the judges.
For what it's worth--
Paul N.