211805051B = LHD from chassisnumber 20 – 117 902 (02/1955)
211805051M = LHD from chassisnumber 20 – 802 986 (06/1961)
Used for models 211 till 273

The shape of this dashboard is used from 02/1955 until 07/1967 but there are some small changes.
When the thickness of the dashboard tray lip changed from thin to thick the shape of the speedo pod also changed.
See the circled pictures.