I was wondering if that was the case. Looks like I have another winter project.Unfortunatly Billy there is no rib close to where the curtain track goes (see photo). You can see the original holes for the headliner to ceiling trim strip in the support rib. That is the outer edge of the headliner. What I did on ours is add a piece of Aluminum stock to the back of the headliner. I bent it carefully to fit at the ends, and carefully added a little more curve across the center to give it a upward spring to provide additional lift. Then I used small counter sunk screws and drilled and tapped the support to match the original pop rivet holes.
As you may remember, we have very heavy curtains, but there is no curtain sag after four years.
I was wondering if that was the case. Looks like I have another winter project.