Hello fellow modding comrade.
I believe this is the best tutorial on the world wide web as of September 2012 to break jail.
And yes, to mod World At War, you will 100% require 2 PS's, which i am going to do similarly in a couple of weeks when the new V1.2 Progskeet is unveiled out of the raffle.
Unless obviously you feel like being dastardly, and relying on codes such as ****PSN.
So in dastardly general, i give the big thumbs up to how you are approaching it.