You need a project leader who can put in the time to pull off a miracle, you've got to find that first. Then you get your developers together, those are hard to find because everyone who can help more than likely already is on one mod or another; keep selection to simply having people show they can actually model or animate or whatever. Get community support behind it, raise money through that and distribute upon first release back to the developers. Because let's be honest here, unless you have a proper amount of interest and motivation to finish what is started it will end up like so many other Battlefield 2 mods which are started every year: dead, all because someone decided to sleep in one day, then realized how fucking monumental of a task it is and for what? Release date 2025, for the sake of a few dozen people to play for a few weeks and that's it.
It would be easier to start a brand new game and go from there, that will solve so many problems, whether it's interest or development.