Yeah, this is discussed here alot and you'll find lots of info on it. There's several good web tutorials on the subject.
I went the simplest way. The CP disconnects from the encoder and then reconnects to the DC. You just reach in and disconnect/reconnect. I didn't bother with a switch or anything fancy. you just need to decide on some sort of universal interface for the CP to connect with (e.g., a DB25 or Molex connectors or whatever) and then wire consistantly.
Have fun!