Well, after months of research and trawling through eBay, I purchased an RNS-E unit last week and fitted it today. Have to say it was amazingly easy as the experts said it would be for Symphony II owners; the vendor sold me the connectors as well as the unit itself, and I bought some removal keys also from eBay which arrived this week.
Below are some brief notes from the install (there are more detailed guides around the web, including some from the excellent http://www.navplus.us website).
First of all, the Symphony II has to come out. After putting masking tape around the stereo to prevent scratching, insert the removal keys (with the longer edge pointing to the outside of the stereo until they click. Have read that some people have had problems with the Symphony being stuck, but with the lightest tug mine came out easily. Be warned though - once those removal keys click in place, you cannot remove them until the whole stereo is removed:
Before disconnecting the Symphony II, I checked that the security code supplied with the manual actually worked - this will help the next owner when I come to sell it. Just unplug the loom and plug it back in again, and the word "SAFE" comes up. Then press and hold down the "RDS" and "SCAN" buttons so you can enter the code:
You can use the four left-most buttons to enter the code. Obviously, in the picture above, I've not yet entered it ...
Anyway, once that was done, I lifted the whole unit out and unplugged all the connectors. Place a towel over the gearlever and centre console before doing this; again, it prevents scratches.
Then, start plugging everything in. The main block is easy; the three different connectors will only hook up to their matching blocks and nothing else:
Next is the diversity and radio attennas. In the Symphony II, these two plug into separate connectors, but the RNS-E receives them both into a two-port connector (forgive me, I can't recall the exact terminology - perhaps CraigyB can help out and I'll edit it!). If you've got the right kufatec.de harness, you have this special adapter to connect them. Mine already had two wires inside it; one had to come out and the Symphony diversity antenna go in, as shown below:
The connector on the left is the Symphony diversity antenna, and the two on the right I'm holding are part of the RNS-E adapter. I removed one from the adapter, and this picture shows the Symphony diversity ready to go in:
The purple piece of plastic is used to secure it - this is it ready to be slotted in to finish:
Once this is done, the radio antenna plugs into the other end of this adapter, so the whole lot looks like this:
Sorry to go on about this step, but it did confuse me for a while and so I thought it was worth mentioning! Anyway, you're nearly there - add the GPS antenna, and then the main block which has a swinging bar to lock in place:
In the background you can see the diversity and radio antenna connected.
You should be able to power up the RNS-E now to test it. Enter the security code and put the DVD in. Right now, my GPS antenna is just above the RNS-E in an alcove above the double-DIN cage; I got 3-4 satellites viewable when the unit was first switched on, but I was between my house and two large trees so it might be okay. Check all this first before pushing the RNS-E into the dashboard as it will save you having to remove it again!
Time to tidy up the wiring and push it back into the dashboard - there's less space now because of the adapters, so be careful. Push the RNS-E home (put gentle pressure around the edge of the faceplate, NOT the screen or buttons) and it should click home.
This thread is a little bit of work in progress, as I will be testing and checking the RNS-E more over the coming week, including whether the GPS antenna is receiving enough satellites, and I'll take some more pictures too. Also got to dig out an SD card and fill it with some MP3s!
Any comments or feedback welcomed!