I think I should have kept it!
I have been looking on the internet (
www.carparts-direct.co.uk) and have found out that steering racks are treated as exchange parts and if done on this basis are about £20 cheaper (£39).
Now I bet they would have taken the sierra rack in exchange for the escort rack.
Too late now the sierra with the rack went on monday.
Might be worth thinking about if you are stripping at the moment.