Finally fixed the intermittent creaking in my steering. I had no play in anything and it was loudest at the steering rack so I was worried it was that. After some exploratory dismantling I managed to work out it was only a track rod end!
It hasn’t worn significantly so there was no play in it, but the boot had failed letting debris in and causing it to sieze up. Some swearing and cutting with an angle grinder later, I have a new one on and no more noise!