There are screws hidden under each switch plate.
The switch plates need to be slid out towards the back of the Hoover.
To do this, press the switch plate down (as though operating it) then look with a torch into the gap you have opened at the top.
Half way along the switch plate you will see a plastic finger acting as a stop.
Deflect this finger with a stiff blade then slide the switch plate backwards.
Chris J
August 2004