One thing i learned from that mission is that take a dive bomber approach goes a long way. Picking a good vector, locking on, afterburners and launch on a good vector to make sure your bombs are on their way and pull up. I've noticed without this approach and just sitting there and lobbing bombs at the turrets that most of the time the bombs just detonate slightly below the beam turret and doesn't do full damage to the tip of the beam (i remember doing only 20% damage with dual helioses once just sitting there lobbing bombs). The dive bomber approach is good because it's fun, it gets your bombs more on target more and more damage done. Usually you want your bomb to hit the midsection of the turret tip and then you'll know you're good.
The other reason the dive bomb approach is a must do, is because helioses and cyclops bombs are slow as hell. What's even worse is their maneuverability. Oh man, i sat back once years ago on this mission, lobbed a helios at the top left sath turret, and the ****ing bomb took forever circling the turret before prematurely exploding and doing only 10% damage, i was like wtf?!?!
The other reason for doing the dive bomber approach. You'll probably beat the mission without needing to skip or cheat on it. That mission really does require precise bombing to destroy turrets faster and sometimes people get all 4. I've only ever gotten 3 turrets on my best try.