if u want u drill piolet holes on the corners of the box, then thru the floor (piolet holes, not large drill bits). go into your fancy toolbox and look for the smallest screw u have, ajust your piolet hole in the truck floor accordingly and then drill into the box (without ajusting it to the screw size). This should work, u can use a fairly short screw ONLY if the box isent shfting a hell of alot