John,
Thanks for changing the title!
Thanks for changing the title!
Thanks for changing the title!
Yeah, using that big plug would be more inconvenient as I would have to remove an access panel on the bottom of the tank surround to do so (about eight screws, laying on your back under the trailer), but on the other hand, that plug would definitely drain the last ounce of of the tank with no chance of a little water left to burst the drain fitting.