If you are doing 380 front then do 380 rear. You need to make sure they will clear the wheel though. If you are tracking I see some people using the smaller size due to using 18" track wheels and tires. Good luck!
If you will be purchasing ANY AT&T services online or in store could you mention that you were referred by me? My Employee Referral ID is eo4489. This would be a great help and it costs you nothing, thank you!