Regardless what published numbers you use, when building pit internals, it always seem to me that some tolerance was needed on the plus side.
Skin and armor thickness used in the build really counts when it come to determining pit ring wall depth. Appears as if every pit wall height has a specific “tallest” greeblie that will help determine this. When it came to floor diameter, there were cases for which some circumference locations required adjustment. Note mandible surface pipe fitting work has down comers that may require rolling a few piping elbows and adjusting T-fitting lengths to match pit equipment penetrations. Another way to say this is pit location and orientation is a function of mandible surface pipe runs.