51 23 131 Adjusting left or right striker on engine compartment lid

Adjusting striker is described in: 

Adjusting engine compartment lid  . See 41 61 014 ADJUSTING ENGINE COMPARTMENT LID or 41 61 014 ADJUSTING ENGINE COMPARTMENT LID .

Unclip anti-twist lock (1).

Unscrew retaining hook (2).

Installation note: 

Adjust engine compartment lid  . See 41 61 014 ADJUSTING ENGINE COMPARTMENT LID or 41 61 014 ADJUSTING ENGINE COMPARTMENT LID .

Fig 1: Removing Anti-Twist Lock

Courtesy of BMW OF NORTH AMERICA, INC.