Another way to remove the nut from the top of the strut: Buy a 22mm deep socket and file a couple of flats on the end of it. Put the socket on the nut, poke an allen wrench down through the hole in the end of the socket to stop the strut from turning and use an open-ended or adjustable wrench to turn the socket. Works in all but the most obstinate cases. Total cost - a few bucks for the socket....