Hi guys,
Well its not an easy job at all, let that be said!
I've removed the factory Japanese nav, plumbed in the audio off the DVD.
I've done this on an Aristo with TV, every other Lexus is different (inc the Altezza) so this won't work on anything else.
I didn't use a convertor in the end, just hard wiring.
One key thing here is that you will have to lose your radio in order to make this work. This is a turn-off for most I appreciate. You could get this to work by runing a switch if you like, something I may do later on if I miss the radio.
Gaz.