All of the instruments I've seen in your pictures thus far are Japanese WW2-era pieces. Each one originally had a data plate, and each plate would usually be stamped with one of three characters denoting its use by service branch:
Anchor - Japanese Navy (usually accompanied by an 'y' symbol, which was added by the Navy Inspector)
Star in circle - Army
Kanji character in a square or circle - Civilian use.
I'm always adding Japanese aircraft cockpit information on my own website at:
index
I make a point of not bothering with common or published stuff - so you might identify some new instrument applications there (and my art

)
- Ron Cole