I have the stock R950 radio cassette with CD autochanger set up in my Disco. Quite happy with it, but would be useful to have bluetooth on there as well. Couldn't find a circuit digram for the radio on the web, does anyone know if this has an auxiliary input that I can hook up the bluetooth receiver to?

Alternatively I could patch it into the signal feed from the autochanger via suitable switch, but I'd rather not....

Whether you use a 3.5mm stereo jack or a bluetooth system, your main problem is going to be injecting the required audio signal into the existing ICE system. There are a number of ways of doing that but no doubt you'll be wanting the best you can get so we'll forget about using one of those tape cassette things and also the plug-in FM transmitters.

The method I've used is a FM modulator, like this device, not to be confused with the transmitter which injects a radio signal directly into the aerial system of the existing ICE set-up with no interference from outside. This also means that all the controls will still work as they should and there's no need for extra switchery. Power for the device can be picked up from the switched output from the radio head unit. The whole system can be housed out of sight in the space under the steering wheel, where the fuseboard is, which makes connections easy too.

Once you have the ability to inject your sounds into the ICE system, then how you get the signal is up to you, either use the 3.5 mm jack directly into the phone, or connect the 3.5 mm jack to a bluetooth receiver.

I was thinking of using a bluetooth receiver, but since I have to plug in a power supply to the phone, there doesn't seem to be any point of dispensing with the 3.5 mm jack plug.

One small problem I did encounter was a whine from the alternator coming up the power line. This was sorted out with an in-line whine filter.

http://www.ebay.co.uk/itm/Connects2-Fakra-Wired-FM-Modulator-transmitter-FMMOD4-iPod-iPhone-MP3-in-car-AUX-/321518729649?hash=item4adc0279b1:g:qLsAAOSwVFlUELPx

Ah, that's interesting - thanks for that Brian. I've seen the FM transmitter type or the cassette version but I've not seen this way of doing it. I'd found a pin out for an Alpine radio on Discovery2.co.uk's page which showed an Aux input, so I was hoping the Philips jobbie had the same arrangement. I could then plumb the bluetooth receiver straight into that. If that's not an option, this would definitely be the way to go.

If you do decide to go with this method, then make sure that you check the aerial connector before you order.
This one will fit the bill:
It has the correct aerial connectors.

Righto, I was just looking up those 'fakra' aerial connectors, not seen them before, but then I've not had a lot to do with car radios for a while now! Thanks for your help.

I put a 3.5mm jack on the front fascia and connected it into the AM input so I could use bluetooth mp3 player. The soldering was a bit tricky.

I can't remember where I got the original instructions from but it's in this thread: http://www.thed2boysclub.co.uk/viewtopic.php?f=5&t=39517&hilit=stereo