welcom to the board jared. there is definetly some cutting and welding involved. The sas requires welding for sure. The cutting can be done with a sawsall for the most part, but it can be tough in some areas. A torch isn't as clean, but it's much faster. Where are you located?
As far as the dual case goes, it depends on the year and model (carb, efi, V6) of your truck.