Hey, so I have a gmc 1500 Sierra that came with 4.3 vortec, I came across a complete ls1 from a 98 trans am with trans and harness, im starting a list on what I need to get/do to get ready for the swap, I hear swapping my rear end to a 8.5 and throw some 4:10 gears should be one thing, what else do you guys think should be next to do or get