Done it!! :D
Piece of cake in the end. If anyone wants pics I took plenty to show my friend how to do it as he has exactly the same guitar, and I could put them up here as a demo.
Found using soft wire was the answer to threading everything into place. Soft enough to wrap around the pots, switch, and jack; easy to bend to shape, but sturdy enough to find all the outlet holes for the various components.
It now sounds amazing, I have a degree of control on my volume and tone (not on and off!), and a solid feel to the switch!