I just inherited this nihonto from my father in law. It was given to him by his father who served in the pacific during WW2. I believe he was U.S. Army and was stationed in the Philippines for a while. I don't know if that's where this weapon came from. I'm trying to figure out if this is genuine and what in general it is. I've tried going through databases, using AI, using kanji translators, and I've been unable to confidently identify any of the kanji. Any help would be greatly appreciated.
Here is a side by side of the mei with the light source in opposite directions. Hopefully all the chisel strokes are visible between the two photos.