Anybody mount a diesel transfer tank like an underbody box?

I have an F550 with a dumping flatbed, I currently have my diesel transfer tank mounted in the bed and have been pushing my luck with it there since I tend to load the truck with material once in a while and the day will arrive when a sharp rock rolls into it and punctures it. I want to mount a tank under the flatbed to the frame rail like an underbody box or a side mount fuel tank but want it to be secure and am looking for pics or suggestions from anybody that's done it. Thanks in advance.....

Anybody mount a diesel transfer tank like an underbody box?