You've started it wrong, you dont need nto undo that bolt. Theres a torx bolt at the very back facing upwards that you can undo (it comes upwards, looks like its not there in the photos so im guessing you have removed)
Once thats un-done you need to slide the housing/clamp off the main shaft that you can see just behind the arms, best way to do that is put the steering at full lock you will see the shaft will be pulled further into the rack, then tap the housing/clamp all the way off.
Depending what boot youve bought you may need to re use the yellow hooked part.
You will need both wheels off the floor to do it.