I came across a collection of old short swords the one on the top has a fantastic blade a tang translation would be most appreciatted.
Another shot at the tang.
Dow-
Strokes are missing from the kanji on your signed blade. FYI, the signature is posted upside down.
As to the attribution attached to the blade in the brass mounts, wakizashi were not made until the early 14th century. If it is a shortened blade, the signature is likely long gone. An attribution to a swordmaker requires back-up with a certificate from a recognized Japanese sword organization.
Bob
Here is what two other Japanese sword forums had to say about the tang marks (The mei is ???? (Doi Shinryo), an early Edo period smith that studied under the famous master smith Inoue Shinkai.) They agree with you on the brass sword.