It's a pretty easy job, but you have to remove the wing vent assembly to get the window out. (This is where you turn an easy job into a weekend-long event) Once you have the vent assembly off of the truck, you might as well take it apart, and put in new glass and new rubber seals. And you will need new glass channels, new rivets for the vent seals, etc.
And a little paint on the division bar would look nice too.
I did mine with no problem, so it can't be too hard. The thing I was most worried about was getting the vent off of the door, but luckily it wasn't rusted on.
I got my vent glass from Chevy duty and the door glass from LCM, and both were very nice. I think LCM sells all of the channels and misc. window liner parts in a kit.