I began to dismantle the wooden box so I can make it the correct size to make the tank fit inside. It wasn't straight forward, easier said than done. The wood isn't in very good shape and kept splitting apart and the nails were so rusted the heads would break off a lot of them or they would snap when trying to pull them out with the claw of the hammer.
Its looks a real mess right now and at this point its probably better to build a new box with fresh wood however I don't have very much wood not only that but this wood is nicely weathered despite being in poor condition. I'm always short of wood so I will have to use what I've got. I will piece this box back together and I will add minimal new wood which I will have to use modestly. It will be a bit of a jigsaw piecing these broken back together so a little more work than expected.
I will go out later and see if I can find any dumped timber.