X3Mech, Thanks for the great post!
I need to replace all the struts and shocks on my wife's 2004 X3 and I only have max 3 hours per Saturday to work on the car so the more I prepare in advance the better. I noticed that on 3/26 you mentioned not having to compress the new eibach springs when installing on the bilsteins: did you ever had to use a spring compressor at all? like when installing the whole strut + spring assembly? What size is the oxygen sensor socket you used ?