This is a major swap. As stated, fuel system, exhaust system, every piece of wiring from the '08, all the computers including body computers, motor mounts, and I think the transmissions are different (not sure if it is a 4, 5 or manual transmission), but it isn't by any means an easy job.These two engines, the 5.9 Magnum and the 5.7 Hemi, I think the only thing the two engines may share is the paint. It can be done, but you need the '08 sitting next to your truck, gut your truck of everything, then start swapping components. It can be done, but don't plan on having it done over a weekend.