I recently built a 496 for my 2000 K2500. With the bigger engine, 11.3:1 compression, and mild cam I figured manifolds and crappy "Custom exhaust" wouldn't do. I ordered up a couple hundred bucks worth of 304 tubing and bends and got to work. The truck has Hooker long tubes, I sprung for the ceramic coating and the driver side has an O2 bung already. Out with the old New stainless tubing and X-pipe, kept the Flowmasters and made a nice simple dual 3" setup. I've got the exhaust mostly on the truck and I'll add some pics from underneath. The way the collectors dump and the truck being a 4x4 meant a lot of little angles and weird cuts to clear obstacles. You can see here the pipe from the driver side connects to the straight section with a v-band. The exhaust comes off easily and should never get rusted in place. I put the factory O2 towards the front of the passenger side pipe and the wideband O2 downstream a bit. For you welding and fab guys I took some pics of the Vband clamp to show the use of Solar Flux instead of purging for welding stainless. The solar flux works well. It does require some cleanup especially if there is anything down stream (turbo, O2 sensors, Etc). In my experience though it ends up costing a lot less than running extra gas through a purge setup. For those that don't know if you are welding V-bands there a few easy tricks to get them right. 1. install the vband flange with the pipe slightly protruding past the flange approximately 1/8" or so. Offset the flange on the other side to have the pipe receed the same distance. This causes a plain vband to "interlock" if you bought the cheaper clamps without their own interlocking tabs. 2. When welding, install the other side of the flange with the clamp to prevent warping. weld it up and let it cool before you remove the clamp. It might sound obvious, But I ruined a bunch of clamps and pipe learning those lessons.