Russian tanks were very light on the markings, and the turret numbers deliberately don’t exactly refer to units like the German ones did. Really, if you put any two- or three-digit number on the tank and nothing else, you’ll be fine. Other markings may have been used, like geometrical figures with numbers etc. inside or next to them, but you can’t go really wrong with just numbers.
The white turret markings, though, should almost certainly be there if your intention is to model a vehicle from the Battle of Berlin. They were air recognition markings, to prevent aircraft from the Western Allies attacking Russian tanks because they didn’t recognise them as “not German”. These consisted of a white line around the sides of the turret and a white cross (front-and-aft, not diagonal) on the turret roof. Usually, this was painted by hand and none too neatly, but leaving room for the turret numbers.
