okay ill come clean, what im trying to do is block prod.cloud.rockstargames.com and send my own JSON to replace theirs with on my ps3 for GTA V.
Ahhh... very interesting, as a luggage problem. (does anyone ever get that joke?)
So, in effect, there is a page hosted on a server you do not own, that you want modified before it is rendered by your ps3. Two options,
one: Proxy the web site with a custom web "handler" which will take http requests, forward them, interrogate responses and update with your customized changes. From a programming point of view, this isn't a very difficult task, but it isn't for the novice.
two: Copy all the documents from the source system to a local web server and modify. This option has serious pitfalls in it, the first being that the source system probably doesn't have "documents" in it, but rather probably asp or jsp server pages etc. That's code, and not likely something you should be copying (or even trying to).