Best way to Prep Stock 5.9 Magnum For Boost?

The OP said he decided on a single turbo, not twins. Remember, he has a stock bottom end so making 1000hp is just not realistic by adding two diesel turbos. His goal could be attained easily with a single turbo by reading maps and plotting his airflow on the chart and selecting one that way, or call a manufacture and ask for help in the proper selection. I would say a 550 hp on a stock short block is pushing the limits of its structural integrity. With that goal you may want to tune it down or add forged internals. But it has been done.