Just as a warning:
Based on my recent experience (Dec. 2005):
1. The '06 LX470 kit won't work in my '05 GX470 (Levinson/BlueTooth). Dealer tried this first, had to remove it.
2. The '05 LX470 kit works great. Delear replaced '06 kit with this, worked fine. We were able to get an '05 kit as of Dec 30th, 2005.
3. There is no interference whatsoever with the GPS functionality.
Enjoy!
-Adam