You have to remove the big plastic headliner cover...be very careful. By now,plastic is really brittle. The mere over tightening of the small screws holding it in place would crack it. My z4 had that part cracked in some places until eventually it just fell off.
I had a choice of buying a new one at $300 or a used whole soft top at the same price. Decided to buy the used working roof instead and swapped that whole roof on my car. Not an easy thing to do if you ask me. :rofl:
It has small screws on the front side near the windshield and one beside the motor. You can see the motor and screw if you remove the cover in the middle.