I wanted to print these in two colors so I needed to split the item. When I did Mesh Mixer could not repair it. I am uploading it here and will give it a shot using the Make Printable app.

All credit goes to Chris420 and the apps... I am just trying to make it do what I want. The one labeled bigb is the final version of the larger casing.

Threads did not quite work perfect, but over all I am happy with the print.