There is a separate aiming mark for the PzGr 39 range scale, a line not an arrowhead; it's at approx the seven o'clock position, in the sight. Of course, you need the sight to be zoomed out, to see this.
PS a couple of mission reports featuring the Panzer III, in stock campaign action and using the STA mod:
http://combatace.com/topic/85352-ste...tock-campaign/
http://combatace.com/topic/87148-pan...riff-ostfront/