WARNING: This page is about a different car, the 2011 BMW M3, 2010 BMW M3, 2009 BMW M3, and 2008 BMW M3. However, it is still accessible from the selected car via links, so may be relevant.
Dimensions in mm
Fig 1: Exterior Body Gap Dimensions And Measurement Point (Front View)
Courtesy of BMW OF NORTH AMERICA, INC.
Fig 2: Exterior Body Gap Dimensions And Measurement Points (Rear View)