Dr. Stefan Bittner has kindly informed me that the line drawings from his thesis on the Achaemenid army are available at his online photo gallery.
Copies of his thesis, and several other books, are still for sale at his press Bodem Verlag. His book is the single biggest source for Achaemenid kit and clothing, and includes some sketches of how equipment might have been put together. Anglophone reenactors could find those useful even if they can’t read his text.
I may address particular parts of his work in later posts, since I have not found much discussion of his book in English.