I think this is the one:
That other guy named Ed and DVs CRII build
http://clubcobra.com/forums/showthread.php?t=87654
Once a thread is started a member cannot delete the thread. Even for a moderator to do so is incredibly rare. Whatever you post is virtually written in stone, forever. Of course you could tediously edit or delete your own posts within a thread, but not the thread itself.