Bose Audio System WHY?  When I found this truck on the dealer's lot it was equipped almost perfectly for me; the only option I would have added was an MP3-capable sound system.  I am not an audiophile by any means, but I did want to augment my AM-radio listening habits with some oldies hits from my MP3 collection.  I tried an aftermarket head unit that worked acceptably, but just wasn't satisfied.  While browsing the local newspaper I spotted an ad for parts from a wrecked low-mileage 2005 Pathfinder; I was interested to find that the SUV had the upgrade Bose audio system and that it was still available.  I knew that the late-model Nissan audio wiring harnesses are pretty much standard, so I figured that the unit should bolt in pretty easily.  The Bose system features a 6-disc changer, an internal amp, and will also play MP3 and WMA formats--perfect for my use!  I'm not absolutely certain, but I believe that this is the same system that is available in the Murano, Armada and Quest.  The unit looked just like new; I made an offer of $150 and was happy that it was accepted.  Now to see if I could actually make the thing work in my Frontier! SERVICE.  N/A.  I bought this unit from a local garage, but I have seen similar ones available in salvage yards or on eBay. INSTALLATION.  I haven't attempted a radio installation for over 20 years, but it was really pretty simple and could be accomplished by an owner with intermediate mechanical skills and basic hand tools.  The entire job took me about 30 minutes, and here's how it went: 1.  I disconnected the battery by removing the negative (-) cable from the terminal.  It's tempting to skip this step, but so many vehicle functions and electronically controlled that I didn't want to risk shorting something out. 2.  I removed the trim piece that covers the radio bay; using a plastic wedge to avoid scratching the panel, I lifted up the bottom edge just above the 12V power outlets.  The panel snaps into place and it is not necessary to remove any screws to get it out--just lift gently around the edges until it pops up.  I didn't disconnect the electrical connectors that run to the panel but I had plenty of room to drop it down and swing it out of the way.  Important note: if you unplug all of the electrical connectors that run to the panel the access will be better, but you'll also disconnect the airbag warning light.  When you re-assemble things it'll blink and drive you crazy until you get it reset.  Here's how things look with the trim panel removed: 3.  The stock head unit radio is attached to a bracket that is held in place by 4 screws; I removed them and disconnected the antenna and electrical connectors and the radio was liberated.  Here's what was left: 4.  Installing the Bose unit was no more complicated that reversing the above process.  I plugged in the antenna, then matched the two plug-in connectors (seen at the bottom of the pic above); everything fit perfectly.  I slid the Bose unit into place and secured it to the four mounting points.  Once again, everything fit easily.  Before replacing the front panel I wanted to be sure that the new unit functioned properly, so I re-connected the battery, turned on the ignition and held my breath while I pressed the power button. 5.  SUCCESS!  I set the clock then tested all the radio functions.  I loaded and tested 6 audio CD's, then I loaded and tested a CD with MP3 and WMA tracks.  Everything worked, so I snapped the center panel back into place.  Installation complete!   RESULTS.  Really nice.  I like the fact that it looks like a factory installation, and even the backlighting is the same as that on the instrument panel.  The sound quality is considerably better that the stock Frontier unit.  I haven't heard the Rockford/Fosgate Frontier upgrade system, but I am really impressed with the sound and features of this Bose system.  True audiophiles might want to try an aftermarket system, but this meets my needs perfectly.  WORTH THE MONEY? Absolutely.  A heckuva lot cheaper than the Rockford/Fosgate unit, and it does everything I ask of a sound system.  What's not to like?