It has instructions on how to install the kit in an LX. Just follow the instructions, noting the exceptions below.
The wiring harness must go down the drivers side of the car, as the GX has the amplifier under the drivers seat. Also, the Sirius tuner fits well right behind the trailer hitch relay in the left luggage compartment panel.
I posted the general guidelines below on another board.
If your GX470 radio has Bluetooth integration then it has the latest software and supports Sirius right out of the box. Just go to Toyota buy the 05 Land Cruiser/LX470 kit and follow the directions, with one exception. The wiring harness must go down the drivers side of the car, as the GX has the amplifier under the drivers seat. Also, the Sirius/XM tuner fits well right behind the trailer hitch relay in the left luggage compartment panel.
Quick directions are as follows.
1)Remove the radio and screen combo from the dash. You only need to pull it out just far enough to get to the back of the radio.
2)Pull back the rug from the amplifier under the front of the drivers seat.
3)Remove the drivers left foot rest by pulling towards you.
4)Remove the left side kick panel and the under dash panel.
5)Remove the step for the third row seat, behind the left rear door.
6)Remove the carpet trim from the left front and rear door openings.
7)Remove the carpet from the luggage area. This involves removing all the floor trim including the trim from the rear door.
8)Remove the rear seat bracket (3rd row only) in the left side luggage area.
9)Remove all the seatbelts that are bolted into the rear left lower trim panel (2).
10)Remove the pocket from the left luggage trim near the seat bracket.
11) Pull out the lower luggage panel. Be careful not to hook the cloth on the top panel.
12)Pull down just enough of the upper panels to get your antenna wire up and around to the top of the rear door.
13)Run the Antenna wire as per the instructions on techinfo.toyota.com.
14)With all your panels off run the harness from the back of the radio down the left of the car, pass the amp wires under the seat to the amplifier.
15) Tie the wires to the factory harness where possible, do a neat job.
16) The amp mounts beautifully behind the trailer hitch relay in the left rear quarter.
17) Test and put it all back together.
18)THESE INSTRUCTIONS ARE FOR PEOPLE WITH SOME EXPERIANCE AND ARE ONLY A GENERAL GUIDELINE> You must get a set of instructions from the techinfo website to augment these instructions. I only illustrate the things that are different between the LX/Land Cruiser instructions and the GX. The plastic parts and panels are easily cracked when removing, and I wont be responsible for anything you do to your vehicle. But if you feel confident, go for it.
I just installed it this weekend. It took about 2 hours and was really not hard to do. The radio is fully integrated. Pressing the AM button gets you SAT 1-2-3 presets. I don't know why Lexus doesn't advertise the fact that this vehicle is Sat ready.
Which years it works for:
I've tested this in a few GXs it seems that the radio that has the TRAFFIC button on the radio itself is the older software and neither the radio nor the screen has the software to support the SAT. If you have a radio that has the Scan button, and the Traffic button is on the Audio Screen then you have the later software and the fully integrated Toyota/Lexus kit should work.
For the older vehicles the only other integrated option is vaistech for XM only.
Rob