Believe your asking about the shock tower reinforcements
You sure? Looked through my pictures and I don't see that they are the same in those
Later Cougars (like 69-70) all were suppose to be equipped with the big block style reinforcements - just what the engineers and Ford wanted and a way to save money on the cheaper Mustangs
67 GT big block Cougar example (they look the same as C code non-GT examples I have pictures of)
68 CJ Shock tower reinforcements