How to remove GSP?

[seaplane]

How can I scrape this off the glass , hopefully in one piece, without hurting it? It's about 3.5" x 3.5.

 

[redfishbluefish]

On the glass.....easy.....straight edge razor. Should come off clean.

 

[Crabs McJones]

How can I scrape this off the glass , hopefully in one piece, without hurting it? It's about 3.5" x 3.5.

Razor blade is best bet.

 

[Palyzoa]

Yup I'd use a new razor blade and work it off slowly.