Thanks for the replies guys. Yes I figured I need to remove the trim to get to the bolts and such.
Is there a guide to remove the trim? I'm guessing I need to remove the grab handles first.
The reason is more aesthetical than technical. I plan to apply vinyl to the roof but the fin is on the way.
It's better to remove it before I lay glass, but if took a lot of work then I just have to go around it.