i can't use my truck tool box in my truck since i put my cap on... and i needed some dry/secure storage on my trailer... i built a frame from some angle iron and predrilled the holes to secure the box to the frame with my drill press. then i welded it the frame. i decided on an exact mounting place and welded the frame to the trailer railing and added a small diagonal kicker for more support to keep it from flexing at all. i sort of got worried when i realized that didn't test fit the frame to the box-- but it fits with an even 1/8" gap all around!!! then i bolted the box to the frame and welded the nuts to the bottom of the frame so they can't be unbolted from the outside! a shot of some flat black paint and she is finished! not too bad for about 2 hours of work!