Right, time to install my Parrot car kit into the new car and thought I'd take some pictures along the way. (bad ones to add).....
Excuse the bad quality pictures, they were taken with a phone and it has been pelting it down all day not to mention how dark it was today.
I've done a write-up on this before but on a different car. See here.
The car is an IS200 Sport from 2001. It might differ from newer or older models but I doubt it.
What you need:
1x IS200/300
1x Parrot MKi9200 kit
1x Sensible person that doesn't do this on a cold rainy day in December!
Tools used: (not many) 
1x Plastic stick
1x Philips screwdriver
1x 10mm socket and wrench
2x Plasters
It was raining today, more like it was pelting it down! I took the gazebo from the hot tub and parked the car under it to keep dry. How dinky does it look compared to the 5? 
First thing to remove is the top of the centre dash. Stick a plastic stick as shown in the picture and the same on the other side. Now grab the unit and pull forwards to remove.
Next thing is the panel with the heated seat buttons in. This just pulls out.
Next is the radio/cassette/CD and climate panel. There are four bolts holding it in. Two at the top and two at the bottom. Undo them and disconnect the two plugs from the climate unit followed by the stereo ones.
This has cleared some room so the first thing I installed was the AUX input cable which is going to live in the armrest cubby. For that the middle console needs to come out and the cubby removed to be able to drill a neat hole.
There are six screws holding the whole assy in.
The leather gaiter for the handbrake just pulls up and off.
Then the middle console just pulls out towards the back of the car.
With the cubby out drill a 20mm hole and feed the cable through. Mr. Lexus was expecting this as he left some handy holes to attach cable ties to. 
The middle console can now go back in and the next thing is the microphone which is going to live just above the rear view mirror.
Take off the sun visor by undoing marked screws and unplug the vanity light plug.
Next is the map reading light and sunroof controls panel. This just pos off and then there's two screws holding it in.
Clip the microphone in and run the cable over the roof lining down towards the A-pillar. Use plenty of cable ties and secure it to the existing wiring already there.
Next of is the SOT lead (more like SOD lead as there's NO room in these cars) Plug it into the AMP (this is where the plasters come in) and the AMP plug into the SOT. Connect the yellow wire straight from the Parrot box to the MUTE on the SOT as a secondary mute or the rear speaker will still be playing music when the Parrot kit is in use.
Cable tie everything to avoid rattles etc.
The blue wire from the SOT goes to any IGN. I chose the cigar lighter as it is easy accessible and it's cold outside... 
Stick a fuse in just in case!
The Parrot control box just fits above the climate panel and I mean just..
Tidy up your mess and grab a beer! 
I wanted the display on the top centre dash but I'm likely to retrofit OEM NAV next summer so it's gone underneath next to the ashtray. The display clears the ashtray flap so that can still be used for storage.
And the cubby to plug the kids iPods in.
Hopefully this might be any use to any of you...