jerztl

ok guys i installed many radis before but i never done a navigation system. Any clues to how this install is it complicated? i see a cable that says speed what does that go connected to?theres also an cable amplifier control +B? Does anyone have pics or detailed instruction how to install this on my car please let me know thanks.
Also i have another question about our car im gonna run a 4 channel amp so i have to rewire the speakers? can we do it from originals front cables to the back or is there an amp that leads to the speakers? i thought the TL speakers amplified by the radio?