Okay, I took a few photos and will try to attach here. First, I have an extended cab. The safe was not made for installing in a vehicle, but is doable. The safe is mounted under the narrower of the two rear seats, each of which lifts up. The safe had two holes in the bottom for mounting. After marking two holes underneath the rear seat using the safe as a templet, and after carefully checking to see drilling there would not cause any issues and that I would have sufficient access to push bolts up from the underneath for small bolts, I drilled two holes. I stuck carriage bolts in thru the underside and into the cab - using large washers on the underside to fit over and handle the square part of the carriage bolt just below the round head. I used duct tape to hold the bolts in place while I went into the cab to stick the safe over the two bolts. Then, used lock washers and nuts I tightened the bolts up and the safe was secure. I use a couple pieces of foam to protect contents from the bolt heads which protrude a bit into the save - could also use acorn nuts as well.
It would take a very ambitious thief to try to pry it out from the inside, or try to unbolt the round headed carriage bolts from underneath. Also, I cover the safe with a bit of black trunk liner fabric so the safe is not readily visible even if you lift the seat.
This is used when I need to leave the gun, or anything else (if small) of value for a short time. When I am in the car and carrying, I keep the gun on me, concealed.
BTW - here is a link to the safe I bought and mounted:
Paragon Lock and Safe Premium .24 CF Drawer Safe for Easy Compact and Sturdy Security: Gun Safes And Cabinets: Amazon.com: Industrial & Scientific
Okay, now to try to load the photos.
[having problems uploading photos. . . will keep trying. . .never seems to be easy for me to do this] UPDATE - the pics finally popped up here. . . .