@glenn at home said: Something like an "Xref" in CAD? It's not automatically updated like an Xref. Perhaps more like redefining a block from a separate DWG file in AutoCAD.

Ok. I solved it through by looking at a new (2022) video och Geil. The option to flatten the base does not show unless you push the small green arrows to the left. Then it was simple to click the flatten symbol under the Misc. head line.The Vector Push Pull seem to give a better result than the Extrude Push Pull.