There are torx bolts that screw into rivnuts (which are bolts that are crimpt into metal like a rivut with threads on the back side.

Of course if you are taking the headliner out anyways, you may have access to the back side of the rivnuts if you have a problem. Unless they screw into a channel you can't access. I don't know exactly b/c I haven't messed with it myself, but you may want to look into it more. I know there are some people here that have messed with it.