Truck Safe

I want to build a small locked box in my truck for keeping my handgun in. I want an electrically actuated lock with a quick release door. And I want to use an Uncle Mike's kydex holster inside.

Lock

The box "locks" with the ignition key of the truck. Specifically, when the truck has power, the box is unlocked. Then all I have to do is press a button to spring the box open. When I shut the truck off, the box should lock itself.

I think a solenoid locking mechanism is appropriate for this. Is it going to draw much power?

Holster

I don't want the gun rattling around inside the box. Maybe good padding is enough. But I had thought about using part of an Uncle Mike's molded kydex holster. It would screw to one side of the box. That way, with the lid open, I could easily wrap my hand around it to grab it.

Location

The handgun needs to be concealed. Therefore, the box itself needs to be inconspicuous. Where can I put this that it will be easy to reach, out of sight, and not in the way? Under the dash seems like the best option. What is under there that I can mount it securely to?