I used a 150 Ohm resistor and used the 5V and Ground on the main board. I didn't want to solder directly to pins 2 and 3 of the voltage regulator but I could have done that instead. The short pin on the LED goes to Ground.
I also made sure the wires did not touch the 'heat plate' surrounding the voltage regulator, which can get very hot.
Edited by rednakes1, Mon Oct 24, 2016 9:57 AM.