Found this site if you need some help.
http://www.oplin.org/databases/proxy...ain.autorefctrenter the generic library card number
123456789
select:
Hudson Library and Historical Society
scroll down and select:
Auto Repair and Reference Center
then you can select the year, make, model, engine, etc.. of your vehicle and access the full repair manuals, wire diagrams, service bulletins, specifications, etc as you need them
TONS of great repair info for LOTS of vehicles, including Duramax engines and much much more.