Worked for me on the first try. Used Memorex DVD+R Dual Layer Media for the ~8GB disc image file from a torrent site. Burned with Nero. Search for "Lexus navigation 9.1" I think, or possibly just "nav" for short.
Tried that. I even paid $30 for a membership to download it because they said they had it, but they didn't have it either. Got a full refund. Do you remember what site? I'm about to the point of giving up. Someone please help.