Devious concoctions has a brief how-to at their site. If you want very detailed plans for that you have to buy their book. It's in their second manual. I have that manual and it looks pretty detailed to me (haven't built anything that complicated). Here's a link to get the book: Halloween Props, Animations, Special Effects, Decorations, and High End Prop Assessories - DC Prop Shop
Here's a link to pictures and the brief how-to (go to the "Un-dead coffin" under Animated Props): Devious Concoctions
__________________ . How-to's for the Beloved tombstone, ancient tombstones, outdoor flicker candles, stained-glass windows, animated spider victim, pallet wood toe-pincher and DMX coffin MiB can be found at my albums:http://www.halloweenforum.com/album.php?u=20959