Re: To cut or not, that is the question!
You may want to check with a local upholsterer, and see what it would cost to have the glass window sewn in with a fabric pocket for the glass to sit in. I have heard of a few people that have done this when they had a custom top put on to replace the original. I would be concerned that removing the plastic rear window would leave stitching holes in the top where the tread was removed. Is the stitching visible from the outside?