People I think have tried to extend the laptop monitor however it tends to loose quality the further you get due to the fact it was never designed for that sort of distance. Also 26 wires that is gonna be a big cable

There are other methods for hooking up to a headunit such as down the ol' FM route. And depending on where you mount the laptop you may need to extend that dvd drive away from the laptop, using like for example an extended ide cable or ide to usb adaptor and running a usb extension.
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Also for a startup solution I recommend using a docking station and soldering 2 wires to replace the switch on the docking station to a relay and using some circuitry to turn it on if it is not already on. There is a schematic of this lurking in the hardware section of this forum.
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