[Ronnie's.930]

If you do a search for "timing chain" you will find quite a few threads that will help (like these) -

http://forums.pelicanparts.com/911-engine-rebuilding-forum/631425-timing-chain-help.html

http://forums.pelicanparts.com/911-engine-rebuilding-forum/622226-chain-fell-off-intermediate-sprocket.html