How the FLIP is this achieved?! There is a massive nut that is about 1/4 of an inch thick which I have no tool suitable to grab with and a 22mm or 7/8th nut that I'm trying to undo. I tried locking the fan and almost bent the blades ... I would cut the nut off but I can't fit a dremel past the pulley without damaging it.
Lock the fan in more than one place. Like 4 places. It is what I did. I had another walk the nut off itself and loose the nut and the key on the highway..
Impact wrench works great for removing the nut and putting it back on.
Find a shop with one.