My verision of the Soul Husks was an adapted version of Dragon Mountain (which Iggwilv had summoned and bound over the physical entrance into the Husks) and a very adapated Labyrinth of Madness for the Husks themselves. Both killer adventures.
The caverns where the final encounters took place where of my own design - not that my players ever got that far, before our gaming fell into a hiatus from which it never recovered.