Lot's of tanks have been used for indirect fire missions. The Sherman was often used in that role but I'm not interested in ad hoc useage of a vehicle.
However..... if the SU-122 ( the old one with the short M-30 gun ) was included in the TO&E of the SP arty units well after the war ended I will be
happy
to include it as "SP-Arty" but not if it was only used in that role when nothing else was available otherwise every OOB would be filled with tanks and SP guns as "SP-Arty" becasue someone could say they were pressed into service like that on occasion.
Bottome line- was it's primary role post war as SP-Arty used in an indirect fire role and not "assault gun" ??
Don