Mike,
First of all, you'll have to drill out the rivets that attach these pieces over the door openings (both styles). For the early style, you'll have to carefully pry up the back end of these pieces (over the rear quarter panels) to remove them. They are held in place by tabs that slide into two part plastic clips.
The back end of the later style is attached with three studs/nuts. The only way to get to them is by removing the sail panels (interior rear quarter panel trim) and dropping the headliner down. Remove the three 8mm (?) nuts that you see on each side, and they come right out.
Hope that helps.
-Rod