Bambulabs style hotend to MK8 adapter Relies on threaded inserts instead of the original nuts and bolts.

The PTFE tube collet should be able to self-thread into the plastic giving a solid connection. It should self-straighten thanks to how the hole has been theaded in all the way, so do not worry about not getting it perfectly straight!

Inspired by this model: https://www.printables.com/model/564990-bambulab-hotend-to-mk8-adapter