I used to have an under seat pistol safe with an electric switch mounted under my dash. The safe drawer was recessed so you could not easily pry it open. When the ignition switch was off, the switch would not work. The drawer was spring loaded so that when you pushed the switch while the ignition was on, it would open automatically. It was the best vehicle firearm security system out there at that time, imo. It was out of sight, weapon secured, but quickly available if needed.
I bought it in 1986 from Galls http:www.galls.com
. I don't believe they carry it any more though. I sold the Chevy K10 a couple of years ago and let the safe go with it.
I figured it would be easy to get another one, but I have not been able to find one since.