You might also want to consider that there are not three pyramids at Giza. There are 8 smaller pyramids (at least one with inscriptions and the coffin of a queen) plus a number of mastaba pyramids where nobles were buried.

Each of the pyramids has a temple complex associated with it. To the best of my knowledge there are no texts in any of these that refer to constellations nor do the texts indicate a star to be associated with it (though they do indicate pharaohs.)

And yes, the "upside down" aspect of the relationship of Giza to Orion was spotted just after Bauval and Gilbert came out with their book. In fact, it was the first argument against the theory given by skeptics who were non-Egyptologists.
[www.catchpenny.org]

Egyptologists and historians and other scholars chimed in, but the "that doesn't match" voices from the public in general (who simply walked outside and looked at the sky) was the first critical attack on the theory.