hey guys, thanks for your help in this. I've just ordered the one that Rayaans' suggested.
regarding the audio update:
I went for the Yatour bluetooth/AUX system, as suggested by a member a while ago, £63 from amazon:
https://www.amazon.co.uk/gp/product/B014R3340I/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1
I also got a Y splitter/adaptor cable, £10 from amazon but you can get these anywhere, probably a bit cheaper:
https://www.amazon.co.uk/gp/product/B00DJ3MHI8/ref=oh_aui_detailpage_o03_s00?ie=UTF8&psc=1
The above items can be used for any Lex/Toyota that has the 6+6 pin setup (2 rows of 6 pins).
If you've got a spare port on the back of the stereo unit, you might not need the Y splitter. Basically the Y splitter allows you to connect 2 devices to 1 port on the back on the original stereo.
My car didn't have the ipod connection, (look in the glove box to see if you've got one).
Removing the stereo unit is quite simple, some good youtube vids out there. You'll need a dash trim remover tool and a socket wrench with a 10mm bit. Probably the best bit of advice I can give anyone on this is, when removing the top 2 hidden bolts, put loads of blue-tac into the 10mm bit, and squeeze it hard onto the bolt. That way you hopefully won't drop the bolt behind the dash, which can be a nightmare to retrieve.
Once the stereo is out, I removed the original stereo connection (6+6 pin), and put the single end of the Y cable in it's place. In the other 2 slots of the Y cable, I plugged in the original stereo connection and the Yatour BT connection.
(there are loads of wires connected to the back of the unit, and you might have to take some out for ease of access. It's easy to do, and because all the connections are different, you'll know where to re-connect - you can't get it wrong! All simple clip in/out.)
Once installed, BT connection/pairing was a doddle, and my phone automatically connects to the Yatour device every time I'm in my car.
You probably know this already, but with the BT streaming from your phone, you can use the car's steering wheel controls and CD unit controls to, er, control the music (track up / down), but you can't with just the AUX in - you can only use the car's volume controls. I've yet to experiment with playlists.
I have to press the "CD" function once to get to the standard CD player, twice to get to the new AUX/BT connection, so I still have use of the original CD player as well.
You don't get the track info (title/album/artist) on the CD screen (boo!) when using the AUX/BT connection - it just says "cd 1 - track 1" all the time, (i don't know if that's a limitation of my cheap Y splitter cable, or because I needed a mp3/cdc switch cable instead of the y-cable, or a limitation of the stereo unit or the Yatour device - if anyone knows, please let us know). And also, you can't connect to the car's original BT at the same time as the Yatour BT - you can only have one or the other at any one time. (this is a limitation of BT in general). If you make lots of calls from your car, then that could be an issue for you, as you can't use the car's large screen display or phonebook contacts. However you can receive/end calls using the car's steering wheel controls if connected to Yatour BT, so it is still hands free, and comes with a microphone.
Hope this helps. It's not a recommendation/endorsement of the Yatour system over any others - it's just one that met my needs at a pretty reasonable cost (£80 all in including the dash removal tools), and, 2 days in, it's still working...
cheers
Bu