Hey, I am qualified for this project as I have been a hardcore GTA fan for a long time and most of the times end up modding it. I made a dragon ball z mod for GTA san andreas once which never got public as it had a lot of bugs but still worked for me. I can help you edit the map. It will take 1-2 days. It's not much of a hassle so maybe I might be able to teach you how to do it in the proccess. Just tell me which GTA map to edit. PS: I got GTA V on my PC so GTA V is possible but not GTA IV.