1) Using a caliper I carefully measured the aluminium top plate shipped with the kit, and drew the design by hand.
2) Based on this my son Christian created a ".dxf" file ( please wiki) using SolidWorks, which subsequently was used
for water cutting the plate.
As the design of the Crack is owned by the Bottlehead Company, I will not share
the files I/we created in the public domain.
If you however have a design in mind, with detailed dimensions, and you need someone to create a dxf file for you,
I will gladly put you in contact with my son, who might be able to help you.