Don,
Since SC brought up my theory regarding the sarcophagus in G1...
Unlike all the other aswan (red) granite contained in G1 the color and granular composition of the G1 coffer is completely different.
The G1 coffer is of the most archaic in its nature, the craftsmanship hardly matches that of any contemporary of Khufu and beyond.
Standing in the chamber you first notice that the coffer appears conceptually different from the work employed on the chamber itself.
In comparison to the coffer in G2, the G1 coffer is poorly made and not polished and is of an entirely different dimension. In fact there is no standardized coffer size, each one from the old kingdom is different from another.
Since all of the chambers and passages of G3 are carved out of the bedrock we find that the original entrance was dug from outside to inside to a chamber hewn from the stone, thus all other passages and chambers are secondary. That original chamber had a coffer recessed in the floor of its western third, in that same area was a pavement, thus the sarcophagus that once resided there was encased much the same way that the coffer in G2 is.
To my great surprise, when I built a model of the G3 chamber with the floor recess (per M&R) the recess dimensions were a perfect match with the G1 coffer width and roughly six inches to spare on either end, however if you were to remove the coffer that once resided there you would need at minimum six inches at either end of the coffer to tilt it out of the recess hole as well to put it in. In addition I found a multitude of photographs of the coffer of G1, there seems to me to be a faint patina discolor on all four sides that correspond to the level that the pavement in G3 as stated by M&R.
The reason the sarcophagus in G3 is missing, as I postulate, is because it was moved in order to cut through its western end to introduce the granite ceiling stones used for the lower granite lined chamber, otherwise it would have blocked the workmans access. As for the coffer discovered by Vyse in the lower granite chamber, It was lost at sea in a storm however the wooden casket inside was recovered and was later determined to have been from the Saite period, also the notes Vyse took regarding the coffer as published by Maspero reveal that it too was artistically re-worked during the Saite period and was of a highly polished blue-black basalt stone. Again pointing out that these features are missing from the G1 coffer.
Returning to the G3 chamber with the floor recess, the subsequent passages were cut from the inside to the outside, from the chamber, and curiously those dimensions adequately accomodate the removal of the G1 coffer if it were in fact once existent in the floor recess. The point being that removal of a sacophagus from the original chamber was better achieved by cutting a lower passage to the north which is what they did, and as Anthony was quick to point out the coffer in G1 could only have been placed there during the construction of G1 as it will not fit through the passages of G1.
I would love to cut a soft styrofoam duplicate of the G1 coffer and attempt to enter it into G3 and place it in the recess.
The above are only part of the picture, it is a conjecture I put out a year or two ago on a different website in the hopes of regenerating interest and perhaps to learn a few things that may disuade my thoughts, so far I am not convinced it is entirely out of the question.
Best Regards,
B.A. Hokom