Below you will find a link to many schematics for 2003 to 2007. This will take you to a folder on my website and you can browse directly to the year and schematic you want to access.
http://www.lt1swap.com/pictures/03to07schematics/2003/ This link will have some 2003 schematics showing cruise wiring for V8 drive by wire, and V6 mechanical throttle. These schematics can be used when doing a V8 conversion in a V6 truck, going to DBW. The cruise has to be rewired to make it work like factory with the V8 drive by wire. Also listed are starting and charging schematics.
http://www.lt1swap.com/pictures/03to07schematics/2004/ Complete engine & transmission controls schematics for the engine/trans harness. These are pretty standard and will work with pretty much all 2003 to 2005 trucks and suvs.
http://www.lt1swap.com/pictures/03to07schematics/2005/ 2005 under hood fuse block schematics. These focus on the fuse block its self and circuits inside the fuse block, ignition switch. Also included is starting and charging, cruise, pto info. This fuse block is similar 2005-2007 from what I've found.
http://www.lt1swap.com/pictures/03to07schematics/2005expressvan/ Schematics specific to the 2005 express van. For some reason, some wire colors changed these years and can be confusing looking at pickup schematics. Some low reference wires, and battery hot wires changed color from the normal used on all other trucks.
http://www.lt1swap.com/pictures/03to07schematics/2006/ Again, complete engine & transmission control schematics for the engine/trans harness. These will be very close for all 2006 and 2007 vehicles, and include the GBCM (generator battery control module) charging, starting, so on.