This is a type of 11 lb. tank that might fit where space is tight. It is about the height of a 20 lb. tank but skinnier, although I do like the look of the short fat ones on a tear. Originally I wanted to put this tank in the tongue box with the electrical gear but later learned that was not such a good idea. We move the tank to the galley or picnic table for use.
The tank mount is my design and build. Two 1/4" rods through existing holes in the base of the tank hold it in place. The tank mount is angle aluminum and Lexan plastic held to the platform with eight screws, fender washers, lock washers and nuts. So far that seems sturdy enough but I still look in the rear view mirror occasionally to see if the tank is still there.