Make a hole

I'm preparing a casting of a muscle-bound body from Braylu Creations for a client's figure.  The casting comes with an open back, but with no hole for the neck.  So I measured the diameter of the neck hole in a wood body (2-1/4"), drew a template on paper, cut it out, placed it on the muscle body and marked the circle.  Then I drilled a series of small holes around the circumference of the marked area.  After that, I used my small clippers to cut an area large enough to insert a saw blade.  I cut around the area and made a hole.

The next step was to use my Dremel to smooth the edges.  Eventually I will cover the hole with soft fleece material so the head will turn smoothly.  The soft fabric will have an "X" slit in the center so the control stick can be lowered into the body.