Good that you have the whole truck, there may be a few brackets that are different but for the most part this is a bolt and go operation. You can use your existing trans/T-case, and computer. Bolt in the 5.3, connect her up and your good to go.
Before you unhook either engine take lots of pictures and notes on how things are routed and connected.
Depending on mileage and condition if the 2000 is 4wd you may give some thought to transplanting the trans and T-case along with the engine.
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