Meanwhile, Graceland is preparing for Lisa Marie's memorial service, which is happening Sunday -- when a huge crowd is expected. Folks have already begun leaving flowers outside the grounds.
TMZ broke the story ... Lisa Marie's gravesite is being excavated in the famous backyard fountain area where Elvis and his parents are buried. LMP's son is also buried there, and she will be buried next to him.
As you know, Lisa died last week after twice suffering cardiac arrest ... first, at her California home, and then later the same day while she was in the hospital. Her cause of death is deferred pending toxicology results.