I drop my G17 in the door pocket of my truck, you'd have to look for it to know it was there, and even then you have to look through the tinted back glass. The white outline on the rear sight gives it away, if not for that I doubt you could tell it was there. Great location for my left hand, but it isnt accessable with my right hand. With a little more movement the Kimber carried at 4:00 IWB is.
My truck has a full bench, with an armrest in the center. About a week after I got it, I got tired of getting my hand stuck between the seat and the back of the cab, so I cut the fabric behind the armrest out making it more accessable.
Due to some broken supports on the driver's side of seat frame, I got a flat piece of 14 gauge (.075" thick) galvanized sheetmetal to replace them (also made one for the passenger side that isnt broke). While doing that it dawned on me that I could also mount my fire extinguisher and maglight on the back of the seat. And after I got it cut it hit me that it would be a pretty good place to mount a holster. I guess I'll give it a try, if it doesnt work, the glock goes back in the door pocket until I find somewhere else.