Ive actually had a question about your swaps,
Say someone wanted to do an ls swap but wanted stay on small budget in the beginning, if you swap in a 6.0 ls, and then down the road want to upgrade to the 6.2 truck motor ls, would there need to be significant changes to the harness that you supply?
All the Gen IV truck engines have the same architecture so interchangeability is good. To go from a 6.0 to a 6.2 would not require much, basically a reprogram of the ECM, BCM and TCM; most all of the hardware is the same.
Try and stick with 2010 or newer engines and transmissions. 2010+ powertrains are for the most part all compatible, they use similar modules and calibrations. 2007-9 LS engines can be difficult to work with because the conflicts they have with specific OS's, it's best to avoid them but we can support them if you have one.
You can use 2 or 4WD 6l80's with our kit, the 2WD does require a little extra work to get to work. We can also support the 4WD 6l90 transmission if you have an Atlas and in some cases with the 241J.