Dara The Tough-Wedge seat wedge
I've thought for a long time that there was a better way than to have to screw something directly into your vehicle and this looks like it. I have not tried it or read much more than what is on the FirearmBlog but it looks promising to me.
That's quite cool.
Interesting. I saw Hornady released their vault last week or so that also uses a similar bladder to wedge it in-place at that location.