Hi EB,
The convertible top material can go under the header bow weatherstrip. I used the weatherstrip to hide the cut edge where the vert top material ended. Vert top material on the front, then weatherstrip, then header bow metal.
It likely doesn't have to go under there, but I think it looks cleaner and I think most shops do it this way. But there I go thinking again LOL !!! I've heard that somewhere.