Forgot to mention, for future reference in case anyone else converts one of these: The encoders are differential "three wire" type, meaning they have A, B, and index outputs.
So each encoders has 8 physical wires connected.... A and -A, B and -B, Z and -Z (or, in the lagun diagrams, "marker") and GND and Vcc (+5v).
I'll post a pic plus the wire color code later, once I get the other axes' encoders wired up.
Erik