Well I got half a result tonight!
I greased the (polyurethane) rack bushings with marine grease (as recommended by the bush manufacturer) and adjusted the clamps tight.
All the knocks have gone from the front suspension, I can go from lock to lock without any noise.
However, the pulling that is dependent on which way you leave the driveway is still there.
Think I'll strip down the struts next.
1980 TR8, coming back to life