Where to get the flashlight adapter?

[newX3user]

Hi,
I am planning to install a Garmin Nuvi 760 into the storage tray on the dashboard (the one with the lid). I have a couple questions on that.
1. To take out the storage tray do I have to take out anything else, or does the dashboard just come out? Is it hold in place screws, etc?
2. I want to power that unit by snaking it through inside of the dash into the glove compartment. Where can I buy an adapter that will convert the plug where the flashlight goes in to a cigarette lighter style socket? I need the regular cigarette lighter socket to charge my phone.

Thank you.