The first job is to have the gearbox half on a work surface as the valve block must be brought out onto a surface at the same height as the gearbox to allow the removal of the Output Speed Sensor.
Firstly, remove the clip holding the Kostal connector to the case..
Push the connector right into the housing.
Loosen and remove all but one the larger headed screws in on the face of the valve block. Do not touch any of the smaller headed screws. They hold the valve block together.
Ensuring the Kostal connector is pushed right in, remove the last screw and carefully ease the block forward. Note the cable to the Output Speed Sensor preventing the block coming right out. Don't strain these wires.
Carefully unscrew the fixing bolt and remove the sensor and draw the block forward.
Note how the valve block is operated by the gear selector.
Note the O ring between the main casting and valve block.
And this washer on the Output Speed Sensor fixing screw. Its position is critical.