How do I replace the pull cord on a Pro polan?

I believe i have everything taken apart but what looks like the last piece that takes the main red plastic cover off. What it looks like is one spring that goes in a circle and 3 metal piece's, two on the out side of the spring and 1 metal piece that crosses everything on top that points left and says off but i don't know how to get it off and i'm worried to break it. Can anyone help me?