mbws400

I have a 91 ls400. Does any one know how to adjust the moonroof? Is there an adjustment on the track, or does the whole track have to be moved? Does the headliner have to be removed?The front edge of the glass sets slightly above the top of the car but the back edge sets about 1/8" below the surface of the top of car. I get lots of wind noise unless i tilt the back edge up. Have not had any water leaks so i don't feel noise is from bad seal.