I spoke with JPC about this. I used to use/recommend around 6.5" higher than the Crank bolt height, and JPC uses the center of the Water Pump.
What would happen was, the results would be about 8% difference (JPC's method was 8~% lower)....so I just decided to keep it simple, and use their method, as it is easier.
What would happen was, the results would be about 8% difference (JPC's method was 8~% lower)....so I just decided to keep it simple, and use their method, as it is easier.