IMPORTANT Legal disclaimer: First, an important disclaimer: I'm not a car mechanic, Audi expert, or any type of other expert. When I began taking my car apart, I understood the risk, and accepted the risk. I knew I could potentially damage the car. I do not recommend anyone follow the steps below unless they are comfortable with them and are willing to accept the risk. Don't blame me if something goes wrong. This is just what worked on my car, and isn't a guarantee that it will work on yours.

Figure 1: RNS-E Upgrade Kit

Don't get me wrong, I love my trusty 2004 Audi A6 Avant. It's great in the snow, and very reliable. But I couldn't help looking on with envy as I saw the newer model Audi's with their bright LCD displays, integrated GPS navigation system, Bluetooth, and iPod connectors.

Then one day it hit me: maybe there's a way to replace the old factory Audi Symphony radio with a newer model. I wanted to keep everything looking factory standard, so that limited my options to Audi genuine parts, and something that would fit exactly right in my A6.

I started my project by searching on the words "Audi A6 Navi Retrofit". That quickly led me to something called RNS-E. Turns out RNS-E stands for Radio Navigation System, and version E is the latest iteration. Even better, turns out you can pretty easily swap out the old Symphony radio for a brand new RNS-E unit.

Now that I knew what to look for, a quick Google search for "Audi A6 RNS-E" turned up numerous online stores that sell the RNS-E. Many places bundle everything you'll need to perform the installation. You can buy the RNS-E for various Audi models, but I needed the A6 version.

You could order the RNS-E from an authorized Audi dealer, and pay 3,500-$4000 for it, including installation, or you could spend around $1,400 and do it yourself.

When I ordered mine, inventory was low, and most places were listing the item as backordered with no delivery date in sight.

Initially I placed an order with NavParts.com. The item was listed in stock, but I received no confirmation e-mail of my order, and they did not respond to multiple emails asking for a status on the order (they did, however, accept payment). The phone number listed on their website is also non-working. Bad sign. They eventually responded, but only after I initiated a PayPal fraud claim.

After getting PayPal to issue a refund for the first order, I tried to order the RNS-E again, this time from Vagnavs.com. Totally different story this time around. The store got in touch immediately, pre-programmed the unit so it was ready to work with my A6's particular configuration (Bose stereo, Sirius satellite radio, multi-function steering wheel). They shipped quickly, and were very responsive to follow-up questions I had when performing the install. Highly recommend buying from Vagnavs.com.

The kit I ordered included the following items:

• RNS-E Navigation Unit
• Plug and Play Wiring Harness
• Radio Antenna Adapter
• GPS Antenna
• DVD with Maps of the US & Canada
• Security Code

Figure 2: Inserting Radio Removal Keys

The first step in the Navi upgrade process is to remove the old radio.

The stock Audi Symphony radio is a double-DIN size unit, and requires a total of 4 radio removal keys to successfully remove the radio from the dash.

The first set of removal keys I tried were the ultra-cheap kind that came with my RNS-E unit for free. Simply put, they didn't work. I tried for longer than I care to admit, but I simply could not get these keys to catch firmly enough that I could pull the radio out -- the keys would just pop out.

At first I was worried that the problem was my radio, and that I might have to bring it to the dealer to have the radio removed. Thankfully, I ordered a better set of removal keys from Crutchfield (shown below), and they worked without issue.

Figure 3: Crutchfield's European Radio Removal Key

Since the removal keys that came with the RNS-E unit I ordered didn't work, I ended up ordering these "Universal OEM DIN Radio Removal Tools" from Crutchfield.

These sell for $10 for a pair of 2. Since I'll need a total of 4 keys, I had to order 2 sets of keys for a total of $20. Annoying, but still a lot cheaper than going to the dealer...

Note that the keys need to be inserted with the notched side facing toward the radio, and the longer side of the key facing away from the radio.

Figure 4: Removing the Audi Symphony Radio

They were expensive for something I'll probably only use once, but Crutchfield's radio removal tools worked like a charm.

I gently pressed each key into the slots at the four corners of the radio until I heard (and felt) the key click into position.

Figure 5: Removing the Audi Symphony Radio

Once all four keys were inserted, I carefully and slowly pulled the old radio out of the dash.

Try to pull the headunit straight out without pulling on the radio removal tools.

Figure 6: Connections Behind Symphony Radio

Once you pull out the Symphony radio, you can see the connections going into the rear of the unit. There are three cables that need to be disconnected before the radio can be fully removed.

1. FM Antenna
2. Diversity antenna
3. Wiring harness (not sure what the proper technical name for this is, but I'll just call it the wiring harness)

Disconnect all three connectors from the back of the radio.

Figure 7: Audi Dashboard with Symphony Radio Removed

With the old radio fully removed from the dash, we're ready to start hooking up the new RNS-E.

Figure 8: Audi A6 Dashboard

This part is the only semi-scary part of the upgrade: you'll need to remove the instrumentation cluster to get access to the V signal (GALA). It also turns out there's an ideal place to hide the GPS antenna behind the cluster.

To begin removing the instrumentation cluster, lower the steering wheel and pull it out towards you as far as possible. Technically this isn't necessary, but it will make it easier to work.

Figure 9: Cluster Trim Removal Diagram

The trim piece just pops right out if you pull it away from the dashboard.

Figure 10: Trim Removal

Pull the trim piece away from the instrumentation cluster. It should come off fairly easily.

Figure 11: Instrumentation Cluster

With the trim piece removed, you can see that there are only two screws holding the instrumentation cluster to the dashboard. They are phillips head screws (already removed in the photo above).

Here's a few important tips that will save you a lot of heartache: be sure to use an adequately sized screwdriver; the screws are screwed in very tightly, and you really don't want to strip the screws. I suggest a P2 size.

ALSO, keep one hand on the screws as you are removing them. There is a gap between the cluster and the steering wheel column, and if you're not careful, the screws can fall down behind the steering wheel column.