The only remaining mechanism to be installed is this latch to release the small drawer. Mortised into the main box beneath the small drawer, the task is straightforward, but requires a delicate touch as this area is quite thin and unsupported.
Latch for small drawer 
Yikes! This is thin!
Since the lever profile varies, let’s begin by determining the location for the bolt to protrude. The center should be sufficient for this application. Next, drill and square a hole appropriate to the bolt size. This allows installation of the latch in the correct orientation to define its outline, providing a guide.
From here, it’s simply a matter of outlining the latch, and paring away the material. It is a slow process, but affords control.
From the top-side, the result looks good, even without the latch plate. Once the drawer is installed, the latch will be inconspicuous, just as it should.
I’d like to thank Josh Huether for working with me on the small latch.
Seems nothing is simple!