Parts List:

m6 nuts - 4

m6x30 bolt - 2

m6x40 bolt - 2

Print Instructions:

Add a pause in the g-code at the top of the nut cavity in the base.stl so that you can insert two m6 nuts and continue the print, encasing the nuts into the part. If you use a 0.2mm layer height this should be at layer 52

The wingnuts could use support.

15% infill seems to be strong enough.