I replaced all three of my windows last summer. Used solvent to release the glue, removed the top which was in good condition and had a boat canvass company I deal with sew in upgraded vinyl windows. DIY: 4 hours and $150 bucks. I have a '95 SL500 and it has a two piece top and I removed the back section to do this. Not that hard. I forgot to mention to buy the MBZ glue (about $30?) to reattach to frames.