Replacing Plastic Window with Glass.

[AndyJF]

The Plastic window on my mk1 has a nasty crack in it so i picked up a replacement glass one from Autocheck.
I understand i need to remove the old window and put the zipper on the new one.

My problem is the old window is stitched to the hood below the zip and i cant sew very well.

Does anyone have any experience in replacing plastic for glass windows and maybe want to lend a hand?
I'm based in South Kildare.