51 47 172 Removing and installing/replacing flap in luggage compartment trim, left or right

Left Side: 

Press release button (1).

Open flap (2) and remove.

Fig 1: Removing Flap On Left Side

Courtesy of BMW OF NORTH AMERICA, INC.

Right Side: 

Press release button (1).

Open flap (2) and remove.

Fig 2: Removing Flap On Right Side

Courtesy of BMW OF NORTH AMERICA, INC.