With regards to the head lining I had mine done and removed the complete panel through the boot, iirc the rear upper seats had to be removed as opposed to just folding them down. It is a bit fiddly but can be done, getting it out is the easier bit, getting it back in is a bit harder as you don’t want to mark or dirty the fresh head lining. Wear clean gloves of some sort, latex surgical or soft material when doing the refit. Make sure any surface that the panel might touch is clean.

the real pain in the rectum part is the Louvre on the sunroom, the panel that slides back and forth beneath the glass, to get this out the complete sunroof mechanism runners and all has to be removed from the car, mine was absolutely rotten, iirc somebody gave me another one which I cleaned and fitted with the help of another PF member, tape up all around the roof around the sunroof to protect the paint if you need to remove the Louvre, iirc once all fixing screws are removed the sunroof mechanism and runners slides out forward towards the front of the car