Below you find a link to pick up a Mopar OEM parts Catalog for not only the Dodge Ram 3500/2500 but also the Chassis Cab trucks. Included is P/N's and breakdowns for the Cummins in addition to the Hemi engines, transmissions, etc.
I'm not sure how long these will be available because the home page says but they are going to be removed but for now they sure are a heck of find and if you own some other Chrysler vehicle like a Jeep, Charger, Dakota or Van they have the catalogs for them too!
MoparPartsAmerica
If and when they are taken off the net let me know because I downloaded all three catalogs for the Dodge Ram.
Merry Christmas!