Im planning on doing it when im rebuilding mine. Hopefully will have a full lecky sunroof soon.
I must admit though - i wouldnt fancy doing it if my car werent in bits. Ive been down there tonight trying to get the lining off the roof without damaging the roof - not easy at all, so much really sticky stuff just wants to pull the roof in with the lining.
After much messing about, had to cut it off bit by bit with a stanley knife. It aint an easy job at all. Roll on putting the new one in!