I have the H&S EGR and Cooler delete kit. For the tuner go with H&S or Smarty, but if you choose Smarty make sure you download the ME version to allow for the DPF delete. A lot of people on here run the flo pro tbe, 5" or 4" just get the muffler. The stock tranny wont hold much if you keep your foot in it all the time. I would get the H&S OD tune or an ATS co-pilot.
2007.5 Mega, EFI by Ryan, Source 2nd gen swap with S472, steed speed, ATS Stage 4 with Co-Pilot, Hamilton springs and pushrods, GDP plenum, H11's, WCC intake and boost tube, Snow Performance.......SOLD! New truck is 2012 Black Laramie mega 4X4.