The pipes on my steering rack were very corroded and sprang a leak. 2nd had z3 racks sell for around £150 but I found someone who sells just the 2 pipes in copper for £33.50 inc vat and delivery.
http://www.powersteeringstore.co.uk/...dels?search=z3
I managed to fit them by unbolting the 2 mounting bolts and the steering UJ. This just gives you enough room to slide it forward to swap the pipes out. The replacement pipes fitted perfectly and didn't need any adjustment.
Might help someone out if they have the same problem.