The lead actors weren’t allowed to see Ray Brower until they unveiled him on camera; this method was used to unsettle the four boys and gain the best reaction possible.
FilmTrivia.tumblr.com recently did a feature on Stand By Me. Check out their blog for all the posts!
This trivia is completely wrong. I suspect that whoever wrote it is confusing us with the cast of The Goonies, who were not allowed to see the pirate ship until they were on camera.
We all saw The Body long before it was revealed to us on the set. Before it was played by an actual actor (Corey’s stand in, Kent), it was a latex head that was built by Mike Westmore in Los Angeles and shipped to location in Oregon. Mike’s brother Monty was our makeup department head, and he spent quite a bit of time working on the head in the makeup trailer. He painted it, he shaded it, he brought it to life (er, death) over the course of many days.
When the head was placed on the dummy body and the whole thing was set up on the set, it was decided (I can’t remember by whom) that the head didn’t look enough like an actual human being. As it turned out, it bore an uncanny resemblance to Corey’s stand in, so Kent was cast to play Ray Bower. They made him up, dressed him in the clothes that had been on the dummy, and put him into the movie.