For the roof. Not sure how yours is made but on my L4240 there are certain bolts that hold the cap. There are others that should remain.
EDIT: I've had my roof off a few times to add flashing lights and replace the A/C expansion valve. The manual identifies which bolts are which. I'm guessing that different models may have different bolts to remove. I did it a couple times by myself but recommend having two people with stepladders or something elevated. The top wasn't very heavy, but it was cumbersome (and they're expensive).