The structure which I discern is based on 5 groups with 3 + (5 + 2 + 5) + 4 = 19 glyphs. The central part has 12 glyphs, and the positions of the pyramids of Khafre and Khufu are at the center, where the new cycle is beginning. 493 + 494 = 987 = 21 (one more than 20 for Moon) * 47 (one more than 20 + 26).

The pyramid of Menkaure is different, which we also can see in the Mayan version of the 'turtle' of Orion:

The 3 'stones' (presumably corresponding to the 3 great pyramids of Giza) are arranged as 1 in front and 2 at the back. The one in front ('Menkaure') has a black spot in front and 4 dots, whereas the other two ('Khufu' and 'Khafre') have 5 dots around their 'mata'.

The 'counters' (black spots) on the 'stones' are 2 * 5 + 4 = 14, whereas the 'mata' on the turtle's shell are 7.

Also here time seems to move forward leaving the cycle of 'Khufu' and 'Kafre' behind, i.e. in opposite order to what I can see in the text of G. Stars with lower right ascension arrive earlier than those with higher and in a way time therefore moves towards the east.