I drive an old beat up subaru that has never been broken into.The interior is thrashed by me and my two dogs playing in the woods.There is just enough trash to hide my cell phone,walki talky"s,camera etc.
Fancy stereos are a big invite for the crank heads easy to trade for the sh**.Dave is right removable face plate is going to be in the car not in you'r vest and they Know it.Just leave it stock if ya can.I installed a couple a hundred car alarms as a kid and trust me they are easy to get a round if not installed by an expert that cares about the install.9 times out of ten the installer will get the power for the alarm at the fuse box which can easily be yanked on the way into the vehicle.Do not trust alarms exept to kill ignitions.
I leave my car unlocked as I would rather replace what little will be in my car than my window.
Get yourself some 8 inch plastic pipe,a cap, and a threaded access glue cap on one end and aceass on the other.Mine is 5'6'' to acomidate 10'6'' rods.
Screw the access plug in untill it is secure.Drill a 5/8 inch hole through access and the plug.Get a 10''by 1/2'' inch bolt,and a 1/2 washer,get a galvie it won't rust, and a small lock.Drill a hole through the bottom of the bolt,big enough and low enough ,to fasten the lock to.Now slide bolt through hole on acesss and slide washer onto bolt and secure lock.My buddy has his secured to his wheel well,in the bed with a couple bolts and steel backing inside the pipe.I have mine fastened to a car rack with steel banding.I dare say you will not break a rod again or get one ripped off.
I have hidden gear in the woods away from my rig before too.Just do not forget it!I have done that before also.