I have a manual 95 SC 300. I have a leaking passenger side problem. I diagnosed the leaking problem by pouring a cup of water down the small hole in the top right corner of the sunroof. You can see the water (at least on my model) pour out much quicker from the bottom of the car on the driver side then on the passenger side(where I have the leak). I then poured two cups of water down the passanger side holehole and noticed the back up ( it appears as if the water is coming out of the plastic mold on the right side of the windshield). I have not yet tried to use the WD40 to clear out the passway, but I know that this is definitely the problem.