It is colder over here on the other side of the mountains: 16. As stated before, I did not have an issue with the power steering on a 73 LA setup. I also went to an electric fuel pump since I put the 5.L magnum in.
I did a lot of research like you are doing before I bought the magnum heads. I was fully prepared to put them on my old 318 but before I could even clean the old block up, the 1992 5.2 showed up so I jumped at it. So far, no regrets.
Patrick is a good source (and for me a great help) for all things 318/5.2L.
Craig