Andrew Suzuki Guitar

On a conductor's score, i have 5 transposing instruments tuned different. The nibori style of guitar playing uses prime guitar (normal tuning), Alto guitar(5th Higher), Bass guitar (4th lower) hence, on the score, i have a staff in C maj, another staff in G maj and another in Abmaj. how can i set the audio playdown to all sound in Cmaj? do i need a plugin? thanks! Andrew