Smith & Wesson Chiefs

[Simson-Suhl]

Hello, I recently purchased two outstanding S&W flat latch Chiefs. I would like the Forum, if possible to post the year of issue date.
Mod. 36 #3511xx, the Mod. 37 #1422xx.
Thank you.

 

[Flint Ridge]

1963-64+- on the 36?

1959 - 60'ish on the 37.

Pictures always welcomed.