Tundradrenalin - i like those diagrams. I'm searching for the car speed signal wire myself. Need the reverse and the speed wire to install Avic D3 navigation system. Seems that regardless of what navigation system you install you need these two inputs for the Navigation system.
I've located the reverse wire and confirmed with multimeter. Driver lift kick panel there's a gray plug ...it's the black and white wire that I've poked the black lead from the multi meter
http://natalisinc.com/05tundradcabreverselightwire.jpg
I'm still a little confused about the vehicle speed signal wire. I don't see the purple/white wire in the diagram as connected to any speed sensor... I'm not good at reading wiring diagrams. I currently have the instrument cluster and glove box out and for access to the ECU wiring harness. If you or someone could clarify for me which wire to tap into from either location for the speed signal I would appreciate it.