The ink is white, it's not very opaque.
The best way to make illuminated plate, I think would be to have the written part totally clear.
Then, apply a colored yet opaque backing to specific areas (depend on what color what what leters).
ie, when the light shines from the back, it'd be colored since its got to go thru the colored backing.
I am not sure about doing this, seems a lot of work for just looks.
It'd be easier just for the logo, however. Perhaps make the lights dance around, etc. I mean, if you want to do it, might as well make it crazy.
)
Thanks!
Nik