The shape, number and configuration of the pumping members has everything to do about the pump's performance. Consider using a FLOWKOOLER PUMP.....it will outperform any stock appearance pump...by moving more gallons/minute coolant at a higher velocity for maximum cooling......I don't think the blade orientation makes a big difference.
If anything the Gates pump might work slightly better since it rotates clockwise.
You definitley got your money's worth out of that old one.