Hi guys
I hope that you are doing well. That is a quite interesting question about an area of the Luftwaffe that is often overlooked ... As I heard on a YouTube video about Luftwaffe ground personnel "No one got the Knight's Cross for greasing an airplane." Nevertheless, their contribution was vital and the ground crews deserve some attention. I was able to find the following document which may be of some interest.
https://www.cdvandt.org/CIOS-XXV-45.pdf
Horrido!
Leo