It is in a closet on a stand in the garage. I have like 18" above the heater before the flu goes through drywall at the top of the closet.
I'm just planning on going up through the drywall. It should come out in the attic not too far from where the attic ladder is, so that will make life easier.
I'm hoping that the weight of the 50 gallons of water will hold it down when I am trying to break the nut free.
I've been researching this for a couple weeks, as my Father's water heater went out a few weeks ago, and I have seen no other way to do it. No way to hold a heater, especially a heater in a small closet.
I just hope my 6 sided 1-1/16" socket, my 18" breaker bar, and the 4' of pipe I have is enough to break it free without damaging anything or rounding anything off. I haven't read any horror stories online about shattering a tank or the anode coming out with the threads. I just plan on taking my time and attempting to go slow.