Yes, marked Mod.36 on the frame.Are you sure it's a model 36 and not a model 37? The frame looks like alloy rather than steel in the pics.
That is what the S&W book said, but my copy is old so I thought maybe information was updated. Did they use both types of cylinder releases at the same time?Well the Smith & Wesson book says they changed from the final design flat latch to the conventional latch in 1964 so yours was made before that. Being a three screw I am guessing your revolver is model marked in the crane area so it was made between around 1958 and 1964. That will be about the closest you can get without having a S&W letter to show the actual ship date.