New arms installed, very easy, only took about 20 mins per side, took longer to get the undertray off than it did to change the arms, completely changed the handling of the car, no more 'weaving' about with camber changes and steering feels a lot tighter.
The bushes in both of the old arms were completely shot, the rubber completely split through.
Have now ordered the other lower arms for each side as well, the bushes are showing wear, although not destroyed, but would rather change them all out to prevent excessive wear on the new arms fitted.
Then noticed I still had creaking from the rear, so took the rear wheels off and checked all the linkages (of which there are many), no significant play, so cleaned them up and a light spray with penetrating oil and the creaking has all but disappeared.
If i'm honest, I'm a bit disappointed with Tesla service, a, for not checking the lower arms when they replaced the upper, and b, for not doing the geometry check when asked (they did a road test instead) as I have gone through a set of Michelin Pilot Sport 5's in under 15k miles.