I put a crossbed box in my dead-sexy '05 F150 today and did it without drilling any holes in bed rails. When I had Chevy or Dodge trucks I didn't really care, but this being an F-Series...well, I'm sure I'm not the only one on this site reluctant to go drilling holes in my truck. There's another piece of heavy steel angle in the middle of the box for the transverse rods to attach to. I used all 5/16" material, but I'm gonna keep an eye on to see if I have to go bigger. I don't really like the aluminum turnbuckles either, but that's all Lowe's had. If I have any issues with this mounting technique I'll let you know.
A thief with a screwdriver could make off with the box and everything inside of it in under 5 minutes.
If they want it bad enough, they'll get it even if you bolt it down, it just depends on how much damage you want them to do in the process.
In the past, I've actually used industrial strength velcro to keep my boxes on. You just stick the claw of your hammer in between the bed cap and the tool box to pry each side up and it comes right out. When it's down, it sits flush so it's tough to tell that's how it's attached, and without tools, it's pretty difficult to pry up anyway.
This method is pretty clever, causes no damage, it's pretty discrete in terms of security, and shows some good ingenuity. Nicely done.
__________________ Been doin' it this way for thirty years!
I use this simple tool call gravity. When the box was empty i put foam sticky tape on the parts that touch the bed. I then filled the box while it was up there.
It has locks on it and i'd love to see a theif try and take the box. It has to weigh at least 500lbs. Didnt need to bolt it in or secure it. The box has never moved an inch, no matter what happens
I've had more than my share of run-ins with gravity. Scary stuff, especially when you get an extra-large dose of it on a motorcycle. Glad to hear that you've found a more productive use for it than I have!