2x6 walls

I'm not really sure I understand what you're talking about. Can you show me some photos of what you've described?

We recognize you have the Andersen Narroline windows. I can walk you through this but you will need the help of a friend. This is not a one-person project.

First, raise the sash and have your friend hold it up. You will see screws holding the vinyl track to the window. Remove the screws and carefully pull and work the vinyl track away from the window. Start from the bottom and work up to the sash as you bend the track, pull it down from behind the sash and out. Now lower the sash and swing it out from the window. There should be enough play to have the sash clear the wood trim.