K11 Mystique with a leaky sunroof

We have a much-loved 2000 Mystique in the metalic gold finish which has the leaky sunroof problem. We've read the forum posts, believe the drains are clear, and have even resorted to silicone sealant around the seals, but still there is a load of water inside the car. We are wondering if one of you experts would be willing strip down and repair the roof, for a payment of course, as we'd really like to keep the car. We are near M25 J6.