I pulled all the windshield trim off the car when I painted it. I was lucky and was able to get the weatherstrip off with out shredding it. The lower trim clips onto the car. You have to gently pry it up a little and then you can pull if off the car. The cowl grill will have to come off first though.
Have you priced the convertible top trim yet? If not when you see how much they cost you will definitely want to paint all the trim instead of replacing it.