the radiator is a new one to me, we used to use the 6L rads as a upgrade for the 7.3.
I read your reply to grit, do you actually have an issue with the rad? personally I would flush/clean it add a antifreeze filter and call it a day unless you are having an issue. another thing to look at if you need a rad, is there not a shop around that makes/modifies rads? there used to be one in every city/town up here but now its a little harder to find them but they are still around.
if you looking for things that fail on the 6.0, the liquid to liquid oil cooler is the biggest failure rate on them and when they fail they lead to over heating and can take out the egr cooler, but I have never heard about the rad one.
