This is a remix of the Bontech Mini. I have modified it to not require any brass inserts. Regular nuts can be used instead. I simply pulled the STLs into TinkerCad and added holes for the metric nuts. I have not tested this and only guessed at the size of the holes because I am not home where I can get measurements. It should be pretty close. I am printing now and will receive the parts to build the extruder from Aliexpress in about a month. (https://www.aliexpress.com/item/32904209624.html?spm=a2g0s.122695126.96.36.199bdd2b04zGE8Sf) If the holes are too large, some glue can be added to hold the nuts in place. If they are too small, maybe the nuts can be heated and pressed in. The hope is that the holes are sized close enough to let the nuts drop in place but not spin as the screws are tightened.
Hatchbox PLA (PETG or ABS probably better)
I am running 100% for a solid no flex part. Almost 12 hours print time at 60mm/s with much lower wall and layer settings. just over 6 hours with 40% infill.