Matt3
You need a considerable amount of patience when removing scratches. The scratch I took responsibility for was an L shaped one, about 12inches in length. Took well over an hour.
Read the instructions and keep the pad moving up and down on the scratch area or you will heat the glass up and can thin it and thus distort the area being repaired. I cannot stress how long this will take!!!
For those of you that don't think a plastic brush edge will scratch glass. Get your daily brush ( one that has had a couple of knocks and the edges are a bit rough) and go to your own front room window. Not rubber edged brushes!!
Right in the middle pretend there is some bird crap, rub the bird crap with the edge and corner of your brush and then post your replies on what happens. You have the link for your own repair!!!!!
Rob