I could be wrong.... but I think you need to pull the engine. I smoked mine in November last year. I'm still in the process of swapping out my engine and from what I've come across, it's a bit of a bitch. Big motor in a lil package (compared to a full size truck) and the headers meet up on the passenger side and there's virtually no room from my p.o.v. but I'm not an expert, just a guy with some tools... haha!