I would buy an 03 or 04 that has 150K+ miles on it and has been trouble free, then immediately do headstuds and EGR delete.
the 6.0s need to be worked. People who daily drive them without towing are going to have turbo/EGR problems. The vanes on the turbo need to travel the full path to "clean". Daily driving won't do this. 05s and later have different software to dither the turbo on startup/shutdown to clean out the turbos.
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Joint Clutch and Gear