Pretty hard turns out...
It seems that this thing was not indented to be disassembled. Not one, but both hands were riveted on. No friction fit, no pin, no nut, but hard attached. I got them off OK though, but it took awhile. Next the paper dial is riveted to a thin piece of sheet metal attached with tabs to the front of the movement. That was fun to get off without tearing the paper.
Oh, and I'm skipping showing getting the glass off, that was not intended to be removed either. [insert long sob story here]. Nothing broken...
So here we are, I've come this far. And now I find that the movement is not a separate removable unit. It is built right into the brass casing with the large oval front. I have to disassemble the movement itself to make room for a new movement. The thing is built like a dollar watch. This is nothing like what I expected. Once I get the guts out, how will I make the battery changeable? I guess we'll cross that bridge when we get there.
I did mention I don't know anything about clocks, right?
I would have expected the winder to be left-hand threaded so you could take it out of the way and lift off the back plate. It just wouldn't go so I gave up and cut off the handle. The back then lifted and the movement came right out as a unit after all. Success!
Now I have the brass cup that forms all of the oval front frame and the back as one piece, plus a back cover. It should be no trouble to put a quartz movement in there. I'll cut the back off completely so the battery can be accessed, and re-use the back cover, held on with some little nuts or something.
I ordered up the movement, so got set aside until it came.