Originally Posted by roadkillrob

I can't tell you how, but you will need to remove the back of the seat as the headrest is on a toothed track with an electric motor driving it - you can see how it all works once the back of the seat is off and it should be easy to figure out, I think you just need to unbolt the drive assembly from the track.

The seat back is easy to remove, 2 spring clips at the top each side, just work your finger under the top corners one at a time and pull straight back until it pops out, once the 2 top corners are out, just pull the whole back piece up to disengage the lower clips.