just a layer of cardboard is more than plenty, technically it needs nothing but places dont like it and will surcharge it if its not covered, an old fridge box has enough cardboard to wrap it
you cant win either way really
mailing something so huge is gonna cost $$$$$
places wont touch anything over 130" girth plus length
only freight place we have here is fed ex and they want over 200 to mail anything that post office and ups wont touch, IE over 130" combined, or over 70lbs
its a bitch mailing larger stuff,
good luck