Prefab3D

Create an instance of a prefab, made by its type: place one with a level or level3DSpawn

Are its parts its children, moving with it as one body

From the prefab's origin to the handle, in the prefab's own space: nothing for separate parts, and for an attached prefab the middle of the box around its parts, where its handle is, as an object's place is the middle of its body

What the prefab's objects made, in the prefab's order

The prefab it is an instance of

Destroy the instance and its parts

Put the instance with its prefab's origin at a place, turned and sized as the handle is: where a level's object or level3DSpawn says it goes; the handle of an attached prefab is then at the middle of its body

Put the parts where the handle is now, making them the first time; called by the handle's update when it has moved, turned or changed size

A prefab's instance has nothing of its own to draw

Keep the parts with the handle, called automatically each frame