Your welcome, what I did with mine was to pry the tab away from the sprocket enough to get a socket on the nut then using a rubber mallet gently tap tap the socket so the tab ends up flatish or to the point where socket is a snug fit on nut, I actually sat on bike with foot on back break to undo nut
Good advice. Think I'll try putting it in 1st with my fat mate sat on it. Back brake on and attack it with the nut runner.