The distance between bust and projector lens needs to be exactly 4 feet.

If you put the end of a tape measure right up under the Ghost Bust's nose and then measure up to the front side of the projector where the lens is, you should get exactly 4 feet.

Now would be a good time to run your cables. The PK20 has several options for connecting your video source to the projector. For example, if you're running the video off of a DVD player, you may want to use the S-video input jack. Or, you could use the RCA jack if you'd rather. There's also a computer input if you're running the video off of a PC.

To keep the cables running to the projector at a minimum, you should run the audio straight out of your DVD player into your sound system, as opposed to running the audio to the projector and then back out again to your sound system. A minimal line run to the projector would include simply the video cable and the power cable.