The more I watch at it, the less I'm convinced.
The difference in dimension between the mekugiana is something that puzzle
me.
Usually multiple ancient mekugiana have roughly the same dimensions
but even ancestral blades mounted in Shingunto are not different :
http://www.h4.dion.ne.jp/~t-ohmura/gunto_023.htm
and Shinshinto handachi mounted swords (Handachi is an Edo period mounting similar to Shingunto, with Sarute) are similar in placement but still with the
same larger dimensions in the holes :
This last has not been shortened. I'm sure because it's mine.