"They have all retired here to the Haunted Mansion. Actually we have 999 happy haunts here, but there's room for one thousand. Any volunteers?? If you should decide to join us, final arrangements may be made at the end of the tour."
I got that from one of the WDW script sites I have marked:
http://hometown.aol.com/tdciago/Scripts.html
The Disney
land version says:
"Oh, I didn't mean to frighten you prematurely. The real chills come later. Now, as they say, "look alive," and we'll continue our little tour. And let's all stay together, please. There are several prominent ghosts who have retired here from creepy old crypts all over the world. Actually, we have 999 happy haunts here, but there's room for a thousand. Any volunteers? If you insist on lagging behind, you may not need to volunteer.
The carriage that will carry you into the moldering sanctum of the spirit world will accommodate you and one or two loved ones. Kindly watch your step as you board, please. We spirits haunt our best in gloomy darkness, so remember, no flash pictures, please.
And now a carriage approaches to take you into the boundless realm of the supernatural. Take your loved ones by the hand, please, and kindly watch your step. Oh yes, and no flash pictures, please. We spirits are frightfully sensitive to bright lights."