Here's my advice:

Write a screenplay of this great story you have. When done, get help from other people in cleaning up your script for a final draft.

Get as much footage from the prequels as you could possibly use for this.

Buy a camera.

Get a group of actors who look like the characters. (actually, the only likenesses that matter are Obi and Anakin)

Get a green screen

Find some locations.

Film them.

Have someone (ady?) help you with visual effects.

Win!

It may seem really hard, but it's more realistic than doing it as a fanedit. You could also revisit this idea in 20 years or so when technology is better. I like your idea, but this idea would need about 100 people working on it, and not just over the internet.

That's my two pence.