The rotate linkage rubs the nod linkage, but it's just a matter of bending the rod arm to clean the linkage..
Here's the first of 3(or 4) build videos, starting with a clean skull, cutting away the plastic for rod clearance.. the videos say it's a 2-axis build, but they are really going to be 3-axis.
Dremel... hmm... Well, if you have a dremel cutter blade or cutter drill bit to actually cut away the area just behind the nose.. because it's plastic, it will melt as you cut it. You might try using a hole cutter(door knob cutter) to cut away the extra. I used the sabre saw to cut a line straight to the front on either side of the rear nose area and tried to cut sideways but the shoe of the saw wouldnt let it go, so I used the drill cutter bit...
I learned that lesson with the plastic coolers I used to make fog chillers. Almost broke my nose. Serves me right for trying to overdo it on quality control.
__________________ So many home haunting ideas and yet so little time.
I am wondering, will a Dremel will work just as well as a drill press for cutting out the bottom of the skull?
I use my dremel with a 3/4" sanding drum to widen the holes out. I draw the outline of hole with a sharpie and sand to the mark. It does it fairly quickly and leaves the holes smooth. Another easy way to do it is with a soldering gun and a piece of #14 bare copper wire as the tip, makes a nice plastic cutter.