51 44... Removing and installing/replacing rear roofliner trim

Unclip trim (1) in direction of arrow and remove.

Fig 1: Removing Trim

Courtesy of BMW OF NORTH AMERICA, INC.

Installation: 

Guides (1) and catches (2) on trim (3) must not be damaged.

Fig 2: Identifying Guides, Catches And Trim

Courtesy of BMW OF NORTH AMERICA, INC.