32 33 ... Replacing decorative strip for sport steering wheel
WARNING: This page is about a different car, the 2010 BMW 528i, 2009 BMW 528i, and 2008 BMW 528i. However, it is still accessible from the selected car via links, so may be relevant.
The procedure is described in 61 31 220 REMOVING AND INSTALLING/REPLACING MULTIFUNCTION STEERING WHEEL SWITCHES (SPORT STEERING WHEEL, FROM 09/2005)