It's just like you thought:
1) take off the plastic covers on the inner wing.
2) unbolt the turrets. Take care, the nuts have a tendancy to shear off!
3) unbolt the damper from the bottom mounting(use a pipe wrench to stop the damper rotating).
4) pull the whole lot up through the inner wing.
5) put the turret in a vice and release the top of the damper from the turret.
Assembly is the reverse of disassembly.
Use plenty of releasing/penertrating fluid on the four turret bolts and the damper bolts and all should be well. The top bolt on the damper may need some localised heat or in the worst case a good 'seeing to' with an angle grinder to remove it from the damper turret. The shape of the turret holds all sorts of mud and water up there for ever.
While you've got the turrets off inspect them closely for rust around the top. It's not unknown over here in damp England for the top of the turret to rust out and the damper to punch through the inner wing cover plate.
If you replace the standard turrets with tubular ones you won't have to take the turrets off again next time you want to swap the dampers.