51 47 ... Removing and installing/replacing left or right underbody paneling
WARNING: This page is about a different car, the 2005 BMW 545i and 2004 BMW 545i. However, it is still accessible from the selected car via links, so may be relevant.
Release plastic nuts. Release screws (1) of wheel arch trim.
Release screws (2).
Release screws (3).
If necessary, release screw (5).
Release screws (4) and remove underbody paneling in direction of arrow.
Courtesy of BMW OF NORTH AMERICA, INC.