I could swear this has been done before.
But have a look in Ianus's Revan's Empire vs. the Rebel Alliance. The Galactic Empire would CERTAINLY own the Rebels, and if you think about it, the Rebels would defeat Revan. Maybe not EASILY, but they would.
Discluding the Star Forge anyway, the Rebels would win, I'm not so sure if it were involved.
Even if Revans Sith did know about the Death Stars weakness, none of Revans pilots would be good enough to make the shot Luke did. "He is the best pilot in the outer rim territory." and "That shot was one in a million." Plus the Sith don't have enough fighters to even get past the Deah Stars defences.