Removing the front upper seat belt

Release the screw (1).
Remove seat belt guide loop (2).

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Loosen screws (1).
Remove the slide bar (2).
Remove seat belt (3).

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Release the screw (1).
Unlock plug connection (2) and disconnect.
Thread out the inertia reel (4).
Thread out the foam part (3).

Courtesy of BMW OF NORTH AMERICA, INC.