water in the oil

Did you change the oil at the same time you replaced the rockers or has the oil been in the engine while you were waiting on parts? I'd pressure test the cooling system but it could just be condensation. I get that milky crap in my oil catch can on my Ram all the time. It sits most of the time. If the cooling system pressure checks fine, then I'd just do an oil/filter change and keep an eye on it.