Trying to service my Fox forks (2005 F100 RLT)

I turn the 10mm nut on the bottom of the left leg, and the whole shaft turns too, so it the nut doesn't come loose!

I have tried holding the shaft still with a screwdriver, but there is little purchase so it doesn't really help.

Any ideas?

Got a 10mm T hamdle spanner ? Leave the air pressure in the fork. Put on the base nut and shock it around with a hammer. 9.9 times out of ten it works. Might need to get a mate to compress the fork

just let the air out, compress it, fix it there with a belt and undo

I tried Mr Frosty's way and that didn't work
I tried Spock's way and the fork seal popped out and half the oil with it!

(Well actually not much oil)

Nevermind. I've cleaned the seals and foam rings the recommended way and that'll do until a proper service or another idea.