So far the factory service manual is the only good source of diagrams for the np241 I've seen...and there's only about 7 pages devoted to that t-case.
Edit: I take that back...those diagrams suck. None shows the internal workings...it's all just like removing the tailshaft and stuff. I can't remember if the unit repair manual has better diagrams, and I can't check because that manual is a home and I'm at school, sorry. /forums/images/graemlins/crazy.gif