To access the connection between the gearbox and the shift rod, there's an inspection cover under the rear seat, just above the chassis number, which, after removing the screw, gives access to the connection.
From model year 1960 onwards, this cover is fitted with a central screw, for earlier years there were 2 screws and the plate had a different shape. Take the correct extra screw if necessary, which is listed in the "options" tab.
The cover ensures that no unnecessary draughts, dust or other dirt can get inside.
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