I did mine years ago, got the one that has the plastic (abs) backer in stead of cardboard. Replace the rubber seal for the sunroof and make sure the plastic guides for the sunroof are good, I replaced and resealed everything in that area and coated any surface rust I found, only regret was not putting extra heat shield like material in there.
Oh and don't tighten the trim screws like they are lug nuts, snug, you may have to go back and snug up a second round later but you won't distort the metal trim.