This part uses geometry identical to the original. I provide a SolidWorks model and a drawing you can use to model this part in your favorite software. I will add new parts to this thing as they are designed.
I've created a base module that will bolt onto the shaft cover of your Thing-O-Matic. This can be used for mounting an adjustable light on your MakerBot.
If you would like to request anything in this series, please leave a comment below. I'll try to get it done for you.