How did they make the "bloody elevator" in The Shining?

[ElectroSunDog]

I thought that the set was a miniature or something until I finally saw "The Making Of The Shining" documentary and the film crews were SWEEPING THE FAKE BLOOD AROUND THE SET. Since Kubrick always kept everything to himself and went out of his way to "destroy the evidence"(ie. burn each and every single unecessary bit of footage that he didn't like) we may never know. Or will we?....

Anyone have any guesses?

[Gunslinger]

Well, just build a set with a watertight closet made up to look like an elevator car at the end (say, line it with clear plastic tarpsarranged so that they'll come apart at the line between the doors), fill it up with fake blood, and open the doors. Simple enough.

[lno]

An interesting aside from imdb.com:Stanley Kubrick, known for his compulsiveness and numerous retakes, got the difficult shot of blood pouring from the elevators in only three takes. This would be remarkable if it weren't for the fact that the shot took nine days to set up; every time the doors opened and the blood poured out, Kubrick would say, "It doesn't look like blood." They had tried shooting that scene for an entire year.