I have checked the physical counters by MMP, in which the SdKfz 10/5 is shown as open topped. That's what it should be classified historically as well. Quote of the vehicle note:
88.1. SdKfz 10/5: The later versions of the SdKfz 10/4 were equipped with the newer 2.0cm FlaK 38 AA gun; these upgunned versions of the SdKfz 10/4 were given the designation SdKfz 10/5. For added protection, 8mm armour plate was added to the front of the vehicle cab and gunshield beginning in late 1942. In 1943 the number of crewmen was reduced from six to four. Photographic evidence and tactical use suggests that leichte FlaK units participating in the street fighting in Stalingrad were likely equipped with SdKfz 10/5.
† These are partially Armored AFV, with armour only on their front Target Facing.
See also German Vehicle Notes
A,
D.
Picture of SdKfz 10/5:
View attachment 18690
Picture of SdKfz 10/4:
View attachment 18691
von Marwitz