Board Thread:Questions and Answers/@comment-7657843-20161007190155/@comment-27837351-20171204171433

The Eye of Agamotto has been referred to as the "Nexus" in several Marvel media, thus fixing the "N" spot. As for the Soul Stone's location, I'd say it might be in Heimdall's chest acting as his "heart", thus filling in the "H" spot.

Keep in mind, the theory was also made for the locations in which the Stones were first shown in the MCU, not of their current locations.