Removing the rear diffuser

Version A:
Loosen the screws along the dotted line (1).

Unscrew the nuts (2) and remove the diffuser (3).

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Version B:
Remove screws (arrows).

Loosen nuts (1).

Guide out and remove the diffuser (2).

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Version C:
Remove screws (arrows).

Guide out and remove the diffuser (1).

Courtesy of BMW OF NORTH AMERICA, INC.