KVA Registration in Germany

Are there any members with a KVA or GTD that have registered their cars as such in Germany?
I am trying to register a KVA but I need a technical date sheet to get the car the first time through TÜV. Neither TÜV SÜD nor Dekra have such a data sheet.
The guys at the test center do not even start with the inspection without that document.

Any information about the registration process is gratefully accepted.

Thank you in advance for your help.