rear window leak

What is your question?

The rear window has a middle slideing window, but thats not the problem. the right window panel is leaking when it rains. i inspected the rubber seal which goes all the way around the rear window, and in the corner of the right panel i can see that the seal has sagged down to where it leaks. There is a plastic molding all the way around the window as well. My question is how do i get the window panel out to fix the seal, and do i have to take the molding which goes all the way around the rear window all the way out to do the work?????