The center of the complex may be MMM or NNN. My thinking is that it is possibly in the MEM Sector. The physical location of the CPU core itself, would most likely not be in CPU Sector, that would be too obvious, as would MEM, come to think of it. The lowest most central location, if the Computer based the coordinates central on itself (Why wouldn't it), Then that may be one of either: MMZ, MNZ, NMZ, or NNZ.