How do you make your buttons light up when pressed?

Hi all!
As a complete newbie to arcade stick building could somebody help me find out how to do a LED button mod with Sanwa buttons?
I saw a few cool video’s on a certain site and would like to try this for myself as it looks really cool! A guy told me i will have to run the LED’s from 3x AA batteries but firstly i need to know how to install the LED’s etc.
Any help/advice would be great!

I found the answer in the custom stick thread a few posts up.

Light-up on activation tutorial with LEDs

Here’s the custom stick thread