There will be a nut at the top of the turret, you can safely remove the whole strut, however when removed you will need to have some spring compressors to hold the spring, BEFORE you undo the nut you will see on the top which holds the top plate down.

So if you have it removed from the hut you just need to undo it from the turret?

Use plenty of penetrating oil on the stuck bolt and leave to set first.

Martin