I would get FRPP 4.10s, although you can also go with Motive. A tune (or tuner) is optional, however you will need to recalibrate the speedometer. This can be done with a tuner or a SpeedCal device.
If you are planning future performance mods in addition to the gears I agree about getting a tuner. You could go with a SpeedCal for less $$ but a tuner is well worth the extra expense.