You have to use the Datascanner to find it. What you need to do is have the Angelwing (equipped with Energy Shells, Torpedos, and plasma guns) tangle with the first two destroyers, and send your two destroyers (Equipped with lasers) after the other two. The Angelwing should be able to bring down the first two, while the others are kept occupied. Have the destroyers target the weapon systems (Start with the energy shells, then hull weapons), and then the engines. After they are disabled/disarmed you can have the Brutus scan them and take out the IP Blocker, or just have the Angelwing destroy them both.