If I was to attempt this myself, and use a ball joint separator tool, do I then need a ball joint press to put it back in?No you shouldn't be able to damage the boot by turning the wheel either way to the stops, You could have pinched it if you were doing any leavering off that area but that's really unlikely.
You should be able to undo the one nut and crack the joint taper from the suspension leg (strut) Then and with a bit of leaver on the wishbone and the leg turned out it should give you room to clear the thread.
Be careful not to allow the leg to come too far away from the car (spread eagle) so as not to pop your driveshaft out.
Most of all support the car well with axle stand as you may need a little pressure to pull the wishbone down and clear.
I would say the usual way a boot is damaged is with either someone getting it pinched with a ball joint cracker or someone using a leaver off that point for whatever reason