I changed out mine on a 2007 2860 DS. Made a huge difference. I did them myself not a huge job but still a job. Did the front one first and had an alignment. Took a short trip and decided to do the rear too. You will enjoy the difference they make. If you DIY being level side to side and front to rear is critical.
Got mine from [URL="http://www.sdtrucksprings.com/"] http://www.sdtrucksprings.com/[/U
The Hellwig bars are a true bolt on job. Had to call for some clarification on one thing and as soon as the light dawned it was simple. Hellwig also has downloadable instructions on their website if you want to take a look before you leap.
You might consider replacing the stock shocks with Koni or Blistiens. Be aware that the fronts can be a bear to do, I had a local shop do mine for $30 and they said never again.