I usually left the spring on but got really tired of stripping the thread out of the plastic nut....
So I bought some of these instead
http://cgi.ebay.co.uk/GPM-ALLOY-STEE...item19b5df000f
Don't use the drag link though as it seems to have lots of play in it but the bellcranks work well. The steering has no give in it after you fit this; however I still haven't managed to kill a servo yet.