i used the stock 5.3 manifolds and completely build my exhaust from the manifolds to the muffler. the tail pipe was cut of a 98 z-71 that had a 5.7 vortec. fit perfect! the piping off the manifolds is 2.5 inch stainless pieced together and welded all the way till about 7 inches from my muffler. actually came out pretty decent minus my welding skills but ill clean them up a bit and just run them until lance finishes the LT's for our trucks. i could probably have a set mandrel bent but i really didnt care enough to try... as long as they dont leak and the motor breaths im happy.
09 CREWCAB LTZ SILVERADO, 6.2, SIX SPEED, CAI,