Yikes! Lighten up guys o.o. Sure, the idea is a tad bit unrealistic, but you don't have to rip the poor fella's throat out for dreaming ^_^.
However, as was stated before a project of this nature would require many, many hours upon hours of work; it is doable in the coding sense, it however is just not overly realistic. I'd say a whole new game (which seems to be the route you are taking now) would be a lot more feasible and cost effective. Also it'd be worth more in the long run, experience wise, at the very least.
Good luck in your endeavors!