Legon follows Petrie's measurements to give a base of around 201.5 cubits. I believe the slope will turn out to be 5:4 and the height 126 cubits, which is the same as the height of the hypothetical pyramid at the 154c level in Khufu's pyramid in Gantenbrink's model for the upper shafts' exits. These dimensions, height and base, are created by a 201.6c base.

Hail Atlantis.