A few links to help you...
http://www.williamsclio.co.uk/forum/...=track+rod+arm
http://www.williamsclio.co.uk/forum/...=febi+bilstein
If you have done the track rod arms in the not too distant past (or are strapped for cash) than just get the ends from a motor factor.
If you have no record or they were done sometime ago best going to ECP and getting the ones listed for the valver and putting them on.
The different between new and old arms is huge and definitely one you will appreciate as a driver.
If doing arms and ends - will need a small stilson wrench to detach the arms from the rack.