Insert the Ping Transducer into the eye slots in the head (friction fit).

Add the led and the photocell. I taped them in place using duct tape.

Here's another view of the head.

Plug the wires into the Arduino.

Here's a better view of the Arduino.

Insert the jack from the power supply through the hole in the back of Ghosty.

Plug the power jack into the Arduino.

Here's what Ghosty looks like tacked together (for now the head is connected to the body using Velcro White Tak Putty).

If you are curious, here's the clay ghost that was scanned and modified to become Ghosty.