I ended up ordering the magnaflow 16612 SISO for my truck today from hottexhaust.com. They had the best deal for me. Far better than I have seen here ironically enough. It will be here next wednesday. I may have to wait to put it on because I am taking the truck in tuesday to have a few tsb issues taken care of. I'll get to know it well before I can put it on! Can't wait!