After much debating I decided to install my streamlight charger in my center console. I tapped into the rear power outlet and realized after the fact that out has power all the time, so I need to find a power source that only has power when the key is switched on. Any suggestions?

 

I used a simple volt/ohm meter and probed the fuse box until I found a "hot" lead with the key on.

When I installed my power windows, I used the power lead of the radio, but as a "trigger" for the relay that I coonected straight off the battery (with it's own inline fuse). Depending on the amp load, you may want to use a relay as well.