You would be better not to open it up, especially that much. Those that do open them up open them by just a few thousandths. The transfer port is usually set at it's optimum by the manufacturer and enlarging more often than not is counter productive.
Isn't it like a garden hose? Squeezing it down you reach an optimal point where the pressure is highest and the water shoots the farthest. Sure not squeezing it gives the greatest volume but not enough pressure.