The first thing you want to do BEFORE you do any kind of programming, is to get gauges. With a 6.0 its a hit and miss with head gaskets, some go with factory tuning, some can rag on their truck with a good tuner and not pop em. The factory intake on a 6.0 is good for around 4 or 500 horse, so you're good there, aftermarket intake just gives more noise pretty much. I would skip the diablo tuning and get an SCT and get some custom tunes from Eric at Innovative Diesel or one of the others, im not the most knowledgeable on the 6.0 tunes so erics is all i know. There are others that are good too.