I think he has them because like a CSL, he has no header panel. His headliner fabric and setup isn’t original. Only the CSL came without a header panel.
I'm not sure what do you mean as the header panel. If this is the "short" panel starting at the upper edge of the windshield and continue over some part of headliner then...
I've seen some non-CSL whithout it
Maybe because they've had the sunroof option?