Thank you all for your valuable information. My first idea as a novice on this Nihonto was as we say in firearms collecting, "bubba'd". The rifle and bayonet accompanying it was in totally different condition. I wondered how did this sword get with this collection of war booty? I have the story about the rifle and bayonet acquisition. I have spent many hours on the WWW researching Nihonto. My search lead me here.
I am not sure if the owner will allow me to disassemble it. I do not even know how. I will not attempt it as it an heirloom. I am sure there are YouTube vids. But I really do not want to buy it if I "bubba" it.
Dan