Servo Size Adaptor (parametric scad)

Inspired by another user's servo adaptor I decided to roll my own after having to hack on his to make it work for my servos. I was trying to use an MG996R servo in place of the HS-805BB servo for raising and rotating the head/neck of my InMoov build but the other upload was giving me grief trying to get the MG996R inside it.

Since I was making my own with OpenScad, I thought I would make it parametric so other people could reuse it to convert all sorts of servos to all kinds of other servos.