According to the 2016 Oklahoma Resident Individual Income Tax Forms and Instructions, your National Guard or Reserve pay is exempt from 2016 OK tax:
"Oklahoma residents who are members of any component of the
Armed Services may exclude 100% of their active military pay,
including Reserve & National Guard pay, to the extent such pay
is included in the Federal Adjusted Gross Income. Retired military
see instructions for Schedule 511-A, line 4."
