Apogee says to to wire the 2 motors together so that you clip on to just 2 wires, like a single use motor. I would guess that this technique would be as close to a successful flight as compared to other rigs.AP clusters are certainly doable, but you have to be aware of the issues involved. AP motors are more difficult to light than BP. And even two motors of the same type by the same manufacturer can light at different rates. CTI motors help alleviate this by putting a BP pellet in the head of the motor and using an e-match for ignition.
As others have said, check the existing threads on clusters for more info.