Ammo Can Bed Mounting

I know there are threads about this but I only found 1 and it didn't answer my questions. I want to get rid of my current plastic box set up and mount 1 or 2 ammo cans in the bed for holding tie down straps and such. What is the best and safest way to go about mounting these? If I drill into the side of the bed how and/or what do I use to mount the cans? Is drilling into the bottom of the bed better? Ideas and especially pictures of setups would be greatly appreciated.