Side Window Seals

Started to assembly the interior on my 70 Dart after alot of frustration learning to paint for the first time. And I was looking at the side window seals/trim and thinking they should be replaced. But it looks like the seals are riveted or spot welding to the door side, not sure about the door panel side because I'm not even sure how upper metal portion of the door panel is removed. The E-body side panels I've dealt were a single plastic piece that was held on with screws. First, how do I remove the inside upper metal portion of the door panel?
Second, how are the seals attached, rivets etc?

Thanks