I am going to build a long range auxiliary fuel tank that will sit between the frame rails under the front section of the bed. Also I have a plan for a rear bumper and 2" receiver built into the rear most cross member. In order to gain access to build these I have removed the box. Two days of penetrating fluid did nothing. 30 min. with a drill and impact hammer removed the heads of the 10 bolts holding the box to the frame.
The I-beam and chain hoist worked like a charm.
The box will likely have to be set back in place to check clearances as I build the hitch and fuel tank but the wife doesn't like parking out in -25C weather sooooo