Absolute doddle although you do need to be able to reverse your head on it's neck!!
It's in the front passenger footwell, pull all the carpets out the way if needed and you'll see a large drum about 150mm diameter. There is one small securing screw and then you turn the whole thing like a light bulb. Out it pops and undo the connection.
Try oiling it as this might work but otherwise get a scrap one as they are quite expensive...over a ton from memory!!