this is a major PITA. I speak from experience. As stated above, use a crescent wrench to remove your O2 sensors before anything, and keep them identified front driver, rear driver, so on. You don't want to mess one of them up and pay $400+ for a new one (although I found some at rockauto.com for like $160 next day shipped from NKG). Patience is a virtue, and make sure you have all the 2' and 3' extensions you need for your ratchets, it's impossible without them.
Your stock gaskets will be fine, just make sure they go on the same way as before
good luck!
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