I used the same strategy that @Waqui mentioned earlier. Be very defensive and heal up when you can and slowly chip away on the enemy. I remember I focused on killing JC first then rex then Ashoka and clone Sarge's last. I used fives, rex, clone Sarge, PLO koon, Biggs as start with JC, Ashoka, wedge backup. the taunt PLO koon can put up on someone combined with rex and AA heal helps and if someone low you move taunt to the then healthiest ship.
Before using this strat I attempted it 100+ times. then a guild mate suggested using plo which I didn't consider since he was weak then. lvl70 ship and lvl 53 g7 toon but using that strat I managed to beat it in the 2nd attempt.