Just like Ed says:
Above The clutch Pedal
Undo the 2x Torx screws of the drivers footwell trim and lower it down.
The Cubby bin under the light switch, nip the sides in and pull it towards the drivers seat. You will see a Torx screw that holds the lower duct pipes in place, remove the screw and pull the ducting out.
The gateway will be up and look for the RED Plug
Unplug it
Prise the Plastic holder away from the metal frame with a slotted screwdriver
and remove it with the gateway in place.
Change the gateway over and reset the plastic rivet which held the holder in place.
And refit it
Just need some patience with this, if in doubt, stop and have a cuppa