I recently acquired this Hamilton 992L, #1657229, 1923.
This watch is before the newer style cases popular with the later 992's and 992b's.
A very clean movement, the only marks I see are a few very tiny marks on the balance cock
The case is pristine B&B Royal, 25 year. No extra case screw marks, only 2 watchmakers marks on the inside of the back cover.
I believe the dial and hands would be approprate for the time period.
The only problem I have is the crown, it dosn't appear to belong with the case. Is it just my imagination?

With as little wear as your very nice 992 shows, the crown is most likely correct for this case. Its diameter fits well into the counter-bore at the top of the neck that is supposed to help disguise its appearance and size, and if the head were any larger it would make it very hard to attach a fob chain to the bow.

Hello Ed- That's a really sharp looking 992!I like the damaskeened winding wheels...The 992's look so much nicer than the 992B's.