In the US, we only have one part number for Eibachs. (at least for now) They advertise a 1.2" (30mm) drop in the front and 1.0" (25mm) in the rear. The H&Rs that I have also advertise a 1.2" (30mm) drop in the front but ended up being a 1.75" (42mm drop) instead.

The install of the springs is really not that difficult, any tuner or specialty shop should be able to do it for you.

Good luck! looking forward to your comments and some pics!

For details, here are the links:
For European and Asian X5:
http://www.eibach.de/index_2.php?LID1=13&LID2=0&LID3=0&LID4=0&MODL=[D]X5%20(X70)[/D][E]X5%20(X70)[/E]&SPA=1&C_lang=en&STEP_2=1&STEP=1&STEP_3=1&HRST=BMW &PRST=[D]Europa/%20Asien%20-%20Katalog[/D][E]European%20and%20Asian%20application%20guide[/E]&STARTLIST=1#

For US X5:
http://www.eibach.de/index_2.php?LID1=13&LID2=0&LID3=0&LID4=0&MODL=X5&S PA=1&C_lang=en&STEP_2=1&STEP=1&STEP_3=1&HRST=BMW&P RST=[D]US%20-%20Katalog[/D][E]US%20application%20guide[/E]&STARTLIST=1#
or
http://eibach.com/cgi-bin/htmlos.exe...28458500027292