If the gland nut is not stuck, you can probably get it with a large pipe wrench. I found with the strut still attached at the bottom and swung to the side, you have a heck of a time getting any torque on the nut as the strut assembly flops around. A pipe wrench would work better with the strut removed and held in a vice. The easiest way is to tap it unscrewed with a large cold chisel with the cutting edge ground flat and a heavy hammer. Soak it with PBlaster good and wait half hour before trying. If it's really stuck, all bets are off and your're in for a long afternoon. Good luck.

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