Hi n0rdlad
I tried some of my friends caps on my Keycool 87II which has purpble lighting, and yes you get light through although it's uneven and the stem and strengthening bits are darker, often looks like the back half of the switch is brighter, not bad looking but not designed for backlighting.
Hope this helps, if you need a picture I still have his Red ESC on my board so will take one when I get home
