A little bit of manual XML editing in Inkscape, and I have servo mounting holes of exactly the dimensions I need. The new PDF is uploaded in the "files" section above. It looks something like this:
I also moved the hind hips higher, to make the femur longer, so that I can fit a servo there. I'm probably going to cut only the legs, and use thinner, 2mm acrylic this time. But this will have to wait until Thursday, when I can go to the FabLab.