Easiest way to remove the clip is with a small, sharp, 90* pick such as the 3rd one down in this picture:
http://www.toolrage.com/ProdImages/MAY-60000.jpg

A small mirror helps you see the clip so you can stick the point of the pick into the small hole in the middle of the backside of the clip, then pull and it comes right off.

Reinstalling the clip... don't. Just throw it away and get a pack of Napa Circular Linkage clips (part number 7352640) for a couple bucks. The clip you need from the pack you can reinstall with your finger tips, as you just drop it on over the top, and push to one side and it slides into place. You can take it on and off vary easily if you want to adjust the Big Head.



Looks like you've already got it done.... but oh well... future reference for whoever else can use it.