Difference between driving forehand and my rally topspin forehand?

I asked this question before and the answers helped but did not give me exactly what I wanted. Right now all I have is a rally forehand with a lot of topspin. I will start working on a driving forehand today or tomorrow. I can hit my rally forehand pretty high over the net and it will go in. My goal is to hit that shot with a little more pace by the time July comes. Now here is what I really want to have answered. On my rally forehand this is my swing. 1.from the ready position with the racquet facing up 2. Turn my upper body so that the racquet strings are facing the curtain behind me and my elbow is bent 3. Lower my elbow and extend my forearm so that my arm is fully extended back(I am lowering my arm while doing this). 4. Now at the moment before I swing up and forward my racquet is WELL below the ball(my racquet is parallel to the floor with the side frame facing the floor and the strings facing left and right) 5. Now I start my swing and swing up and forward with the butt cap leading and finish with a windshield wiper finish. That is my heavy topspin rally shot. NOW HERE IS MY QUESTION!! For a driving forehand do I still get below the ball or just stop my backswing with my arm fully extended back and parallel to the ground at the level of the ball and swing straight through? Also do I use a windshield wiper follow through or just a regular catch the racquet up near the head finish?