Ulmo

There is an unacceptable squeek over my head somewhere above the sun visor. I know how to remove the rear view mirror and the switch plate parts around it, but I confirmed the squeek is to the left of that, and I have not been able to locate it or stop it with any type of object, pressure, light, mirror or camera, regardless of how I reach in there.

I think I need to remove the clothed cover to identify and kill the squeek. How do I do that and put it back with no damage or acceptable results?

I already removed the sun visor clip and mirror bracket, but the cover remained tight.

Here's the cover, left of mirror and switchplate, reassembled of course:

Ulmo

Sigh. No response to this yet. I've noticed the temperature, amount of driving, and bumpiness of road all affect onset of this horrible squeeking noise. In California, that means lots of bumpy roads (communism sucks).