I did my sunroof recently, I have a 535is that was rolled this has been a project vehicle. The forward headliner board isn't bad and goes back with out looking like it was removed, ie. easy fit. Anyway, will the sunroof roll back if you loosen the drive clutch and use an allen wrench to manually move it? If so then revoming the headliner board is simple and must be done to see is the drive gear is missing teeth or to see if the spined cables are damaged. Being in Texas I can't help with a good wrench in PA. I've heard that someone who does good headliner/interior work will know more about sunroofs, stess on GOOD WORK. lol.