This is one of those grey areas as to what should have happened and what did. As troops left for Africa they were issued tropical clothing from either Heer or Luftwaffe stores, these would already have the appropriate style of national emblem and collar patches applied. Rank was then added by the wearer, this should also have been tan but there are numerous examples of temperate clothing rank badges applied (the shoulder boards) as often the Tan version was not available. There was NO specific panzer crew collar patches for Africa, the only examples of the panzer skull I have seen is the metal badge pinned through the ordinary collar patch.