To add The Nav on The W211 One MUST install a Nav drive in the trunk..
that requires a special bracket and molded left side trunk carpet..and a spliter for the nav unit..
The correct way re the Xeons is to replace the COMPLETE headlight assy to a factory mercedes xeon head light ...
added a few items to my 2006 E350.. Steve @www.mbenznl.com
here is a list of the Mods added after I purchased the car..
220 parktronic
289 wood leather steering wheel (with leather airbag)
388 UHI phonesystem
390 voice recognition
401 ventilated seats
433 drive dynamic driverside seat
434 drive dynamic pass side seat
443 heated steering wheel
475 tire pressure monitor system
500 power folding sidemirrors
527 euro DVD comand with nav drive
614 bi xenon headlights WITH functioning auto levelling feature
810 HK soundsystem
860 TV tuner
881 trunklid closer
882 interior motion sensor
link and pics
http://forums.mbworld.org/forums/showthread.php?t=124766
Great prices !