Can you convert 4 to 4s?

I have an odd question, I got an Iphone 4 from a friend of mine, and he had broken the digitizer, so he gave it to me. Recently I hopped off my parents plan to my own pay as you go plan, with ATT and needed a phone so I started using the 4. Needless to say I would like to replace the digitizer, but I'm wondering if there is a way to do more. By more I mean upgrade perhaps the logicboard, storage, and camera to 4s specs, which would allow for siri, better photos, and a few other things. Is this even possible? Upgrading the whole of the internals from 4 to 4s?