Thanks for the suggestions guys.
I'll dig out the printout from the latest alignment tonight.
Both front, and one rear bearings are new 'ish, but I'll check them at the weekend. All the brakes are new. The tyres are all new, and the front ones were put on the car just before the first alignment (which was front only). Thats when the problems started. It feels like there is little or no power assistance when turning left, but plenty/enough assistance turning right. The wheels dont turn themselves in the air, though, so I dont know what to think.
The steering rack has been rebuilt, and one of the signal lines to the rear steer was replaced. I thought it might have air in the rear steer, but apparently it will bleed itself. (Boy did the suggestion that it wont cause a war!

). The power steering fluid level doesnt change with engine on or off, which would suggest no air in the system.
I have the OEM wheels with good'ish tyres on, so I might try going back to standard wheels, just to see if the problem changes or disappears.
Does anyone know if the front strut mounting swively things are handed? Coz I changed 'em for new ones, and didnt see any difference between them?
The 4 wheel alignment showed everything was within tolerance, except the rear camber, which wont cause a pull. And the centre line thrust angle was 0 degrees.
I'm wondering if the power steering pump is the problem? Anyone know if it has two output lines, or just one?
I really need to sort this, the car drives like a pissed dog!
I hate it!
Cheers,
Paul.