If you want to solder the LED directly to the board, solder the resistor onto one of the pins and put the other LED pin in the right hole and the other resistor pin in the left hole. When you get to the point where you check out, if the LED is working, and you find that it doesn't, the you unsolder the LED/resistor pair from the PCB and just keep them soldered together. Then turn it around, and put the resistor in the right hole and the LED in the left. It matters, which LED pin goes into which hole, but it really doesn't matter, if the resistor is in one hole or the other.