AC oil help.
I just replaced my AC compressor and accumulator. I have a 2001 Ranger V6 4.0. They system takes 30 oz of refrigerant. my question is with the oil. The only thing i could find on how much oil to add was to drain the oil in the accumulator and add 1 oz. that worked out to 4 oz. The refrigerant i bought has oil in it. I got 2 cans one 19oz and one 12 oz. the 19oz one has 3 oz of oil and 16 oz of refrigerant and the 12 oz can has 1 oz oil and 11 oz of refrigerant. that is 27 oz of refrigerant. so i guess my question is do i need to add 3 more oz of refrigerant? or is the 30 oz that is required for the vehicle include the oil. this is my first ac job. Any help would be appreciated.