Since you've got a cool dude to weld some stuff up, then use some tabs on the drum for loops that your straps can hook to. I would think that is sufficient enough, provided enough tabs and sized appropriately, to mount the drum relieving the need of a cage. However, the cage is still a good idea.

In addition to that metal work and that the tank will be on its side, then is there any intent to cut large hole in the top side? If so, cut it enough to weld in some plates (thin) to make baffles. That will take care of the sloshing for when not frozen. Lastly, install a breather valve for pressure equilizing if intended to button back up tight. Otherwise, I don't seen any reason an access hole would be a problem. Refill or remove as desired.


Depending on type of snow/ice conditions, in addition to tires, weight in the back of these trucks remains a good idea. Spreading some weight is your friend.