I don't slice much, as a matter of fact, I push in most shots.
My club face is pretty closed at the top, my left wrist is flat not cupped, the over the top happen all the time during the downswing due to IMPROPER BODY TURN, it dont spin my right shoulder out for long time ago - otherwise it will slice. Do you need to do anything with your right arm to avoid over the top, I mean do you need to train your right arm especially the motion of forearm release and elbow setting? I found these elements control the arc and plane quite a bit, if not all.