Do you offer mounting brackets for these tanks?

No, we don't offer any mounting brackets. There are two ways you can mount this unit. The first is with straps. The second is with bolts that screw into the 4 molded-in inserts on the base of the tank. With the application you are talking about, the second option would work best. If you need more detail on this, you can always call us or speak to your nearest dealer. Thanks for reaching out.