I have a Pan Am 64M alto serial number 46676, that Badenia says was made in the 1930s and it has a microtuner neck, unlike the Conn design and a bit different from the pics in the posts above.. Years ago I posted a raft of photos of it on SOTW.
Here's the link to those photos:
https://www.saxontheweb.net/media/albums/pan-american-alto-model-64m-by-conn.884/
If that doesn't work I can try to repost some of those pics here. Meanwhile, here is the neck and microtuner.
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