i have 06 as well and been trying to buy the front and rear guards...i saw a couple listings on ebay saying they fit...i tried to buy the one from nissan and courtesyparts.com said it doesn't. that leads me to suspect the mounting points are different and not sure if the ebay ones really fit...nobody seem to know for sure.
I specifically asked about fitment on the 06 murano and I let him know that nissan dealers are saying the OEM nissan bar does not fit the 06.
"Hmm I haven't heard from our customers about compatibility issues, but our technicians check to make sure that they DO fit on new models. So I can assure you that our guards DO fit the 06 model including the FrontRunner and the Rear Bumper Guard."