[944Spec_bound]

Wait....
If the struts are out of the car and the springs are attached.....STOP!!!
The springs are still loaded and need to be compressed. If you just remove the top nut it'll end in tears. Seriously, I hope you haven't done it yet!

If your still with us, go rent a spring compressor and remove the tension. Then you can try this to remove the nut....

I didn't have the right tools, so I used what I had available. An allen socket for the shaft, a deep socket for the nut, and a pipewrench. I put a 3/8 extension through the square hole of the deep socket, attached the allen socket from the inside. So now you can turn the shaft with a 3/8 ratchet. Then I held the nut with the deep socket using the pipe wrench from the outside.

I did it this way a couple of times now. Or you could go buy the deep offset wrench designed for the job.