I wanted to do something different for the Rex head because scale wise, compared to the Raptors it would have been quite larger. Instead of trying to do the obvious and just scale things up, I decided on a totally different route and made a Rex Fascinator, or little hat to sit on top of the head that had a thin elastic band to keep it on around the neck. Then I made a neck corset out of red faux leather and added a row of teeth on the top of it. Additionally, the costume had a white elastic harness like the other dinosaurs. Unfortunately I don't have any detailed shots of the collar or harness but you can see how it looks in the live shots.
Some shots of the live show and full costume: