its prettysimple, fairly cheap, and kinda time consuming on the vortecs. New cap & rotor, wires, plugs, oil, lube, all filters, check/replace things like the PCV valve, EGR valve, and all hoses/tubing/belts. You can also ceck brake pads/shoes/disks/drums, rear end oil & gasket (and check fornt transfer case/cv boots). They also recomend compression-checking the radiator and checking the air conditioning system for proper freon levels. Add some fuel system & injector cleaner and a top it with a silly air freshiner for the cab and your done.
-Ut