Reduced the set to 3 parts; better press-fit for nuts or screws; better fitting of lid and housing (maybe use a drop of superglue to get it close permanently)
You may use these things with screws and/or nuts or even together.
Printed in ABS, 0.2mm, 20% infill circular, 3 top/bottom layer, 3 perimeter. Probably no scaling necessary.
Printed in ABS, 0.2 mm, 40% infill, 3 top/bottom layer and 3 perimeter. If screws and nuts don't fit for you, scaling things to 110% may help. (I'm working on some dimensions ... )