Add LEDs to 4x4?

[gabrielreygoodlatte]

Hi! The 4x4 board looks great -- very close to what I need. I'm wondering if you think there's a way to add per-key LEDs? It doesn't look like LEDs are integrated into the circuit or that there are cutouts for LEDs on this (is that right?)

So, a couple questions:

• How hard do you think it would be to add cutouts for LEDs so that I could build a matrix under the board?
• Would there be some other way of building an LED matrix on top of the board?

If you created a version of this with integrated, addressable per-key LEDs, I would be very, very interested. Essentially, I'm looking into building a monome / grid controller (for music) with mechanical keys.