You are still using 1040NR, when your 485 got approved? You are so lucky! Because most of us already long pass the mark line of using 1040NR. We were "Permanent resident for tax purpose" before 485 approval and after staying in this country for more than 5 years.
You can use any one among 1040EZ, 1040, 1040A, depends on how complex your tax is.