Re: To cut or not, that is the question!
Some people have gone the route of having a plastic window sewn in. As long as it looks OK and doesn't leak I would leave it alone. Of course you won't have the heat element in the rear window now. You may get rid of most of the noise by driving with the windows up. Even roadsters with glass windows do exhibit a lot of rear window buffeting when driving with the windows down. You also might try a wind restrictor, that might help. Just my $.02