I've sent off the PCBs for rotors I, II, and III.  They are very similar, but the pads on each side of the PCBs are routed / wired to scramble the letters in different ways.  The Wikipedia page is a good resource if you're interested in how they are routed.

The other bit that differs on one side of each rotor is the turnover notch position.  This is currently just designed into the 3D printed part.  There will be 6 different parts that will work with the 8 different rotors since rotor VI, VII, and, VIII share the same turn over notch position.