True Bypass Looper housed in EHX Holier Grail

[insomniac2295]

Hey fellas, first time poster. I cracked open my EHX Holier Grail today and found that only 50% of the enclosure is taken up by the pcb. I want to house a True bypass looper in it to save room on my pedal board. I'm thinking of putting the in's and out's for the looper along the bottom strip, just how the grail in's and out's are along the top strip. My only question is: How can I run an LED off of the already existing 18v power?

Now for some pics for reference:

[thedefog]

Supply Voltage (18v), minus the voltage rating of the LED you plan to use (Standard Red is like 2v) = 16v, Then divide that by the current needed to operate the LED (20mA generally, but may vary in your case) and you'll have your answer.

For a standard red LED running at 18v, you'd want a minimum of an 800ohm resistor, or just use a 1k. That'll give you a nice bright LED. You can use a larger value as well, like a 4k7, but it won't be as bright.