I am new to auto restoration work, and have never polished auto glass before. I have a 1969 Mustang Mach 1 and the rear (tempered) tinted glass has several long scratches deep enough to catch my fingernail. I bought the deep scratch kit. The glass has been removed from the car and I am ready to start polishing. I’d like to keep the glass because of the Carlite marking and date code. Some people told me not to bother polishing the glass because it will shatter for sure. I understand that I need to use low (2500) rpm polisher speed and use water to keep the glass cool while polishing. Are there any other tips you can provide before I make a costly mistake and shatter the glass? What is the best way to evenly remove the glass material all over the window as I am polishing to as not to get visual distortion in the glass?