You can get if out of the drivers side wheel arch with the pulley on and the right angled metal pipe, but it's bl**dy awkward and took a while for me to do.
I found it easier to put it back without the metal pipe on and then attatch that with the pump mounted up.
You'll need a 14mm long reach socket (makes it easier anyway) to get to the bottom mounting nut at the back of the pump.
It's fairly straight forward, just slightly awkward for the reason above. It took me longer to get it in and out of the wheel arch than to do the rest of the job. :evil:
A vice would be handy to hold the pump to undo the pulley nut and to do it back up.