A Bergepanzer was strictly a tow truck and had no room for AA weapons. Vehicles carried a single 7.92 cal MG for protection,. The AA vehicles were outfitted with the number of weapons needed and all space was used for crew, ammo and weapon related gear. Can't make a dual purpose vehicle out of a bergepanzer. Would be nice to have a Flakvierling in the area while you were pulling out a disabled Panzer.