RE: 4.8v vs 6 volt servos
Flypaper 2 is basically correct. There is no difference in the way you hook up a 6volt system vs a 4.8volt system.
You do need to pay attention to your flight pack and whether it is compatible with un-regulated 6volt systems. Some Futaba and JR servos are strickly 4.8volt applications. I'm not familiar with Airtronic systems. I know Futaba has a servo/gyro combo that will only run on 4.8volts. I do believe all of Hitec flight pack systems are compatible with 6volt without regulators.