Beginning Air Abrasive Cleaning Cryptolithus Trilobite

Yesterday, I posted some images of Cryptolithus trilobites found in the Kope Formation, Carroll County, Kentucky. The visible part of the fossil (see last photo) could be seen on both sides of the cephalon. I decided that the middle could be air abrasive cleaned along with an engraver. As you can see (first two pictures) the whole bottom rim is now visible along with some of the inside shell. Whether the head plate is intact remains to be seen. Also part of the genial spine emerged.

Another part of the rock, yesterday I speculated part of a starfish arm might be visible. I am now wondering if this is just an imprint made in the matrix by the holes along the cephalon plate of the Cryptolithus.