I remember using years ago a professional-grade product I was given by the shop who painted my Camaro to take off paint overspray on glass. I used it for several years with great success to remove stubborn tree sap from the windshield.
I ran out of it and since it felt like a paint polish anyway I decided to try some today. I used some fin-cut polish on my Fastback's back window... It worked wonderfully. The glass is now smooth as... glass!
I moved on and did all windows and also the inside of the back window, which needed help. No hazing, no scratches...
Try it with a fin-cut polish and it should work out fine.
I ran out of it and since it felt like a paint polish anyway I decided to try some today. I used some fin-cut polish on my Fastback's back window... It worked wonderfully. The glass is now smooth as... glass!
I moved on and did all windows and also the inside of the back window, which needed help. No hazing, no scratches...
Try it with a fin-cut polish and it should work out fine.