Useful guide and good photos, thank you.
I'd just add:
1. There's no need actually to remove the metal circlip; just pulling it back a little with that flat screwdriver should be enough to enable you to pull the strut off the ball.
2. The bit that says "If you don't, when you remove the struts it'll drop on your head" needs to be in bold capitals for people like me who are inclined to forget the prop when they go out to the car and are too lazy to go back inside to get it, and say to themselves "Oh, surely it'll be all right - can't be as heavy as that..." Oh yes it is. It WILL fall on your head - even with one strut still in place.