np203 diagram found here:

[wild03]

Here's something missing from the chilton book:

For those interested on a blow-up diagram of the np203
I found a nice one online at
www.gmpartsdirect.com

just put any bogus number on the parts search, and you should get a link to the "new alternate catalog" there you can select any truck that came with the np203 I tried
1977 GM pickup:

select "transfer case" -> "transfer case assembly" on the left frame then np203 on the right frame.
and you should get a list of part names and numbers, click on any part name and you will see a "view graphics" option with the number for that part in the diagram.

Click on the number to see the diagram!

Hope this helps someone!