Well I got mine done, they're not as sexy looking as your round ones are going to be but I like them.
I went for a pattern instead of a grid layout, this worked against me in the end as I couldn't fit as many of them into the allotted area as I would've liked, but there's no reason why I can't make another set in the future.
They're mounted to a metal panel that's painted silver so behind the lens they are almost completely invisible when they're not on... it also hides my horrible cutting and bending of the metal to follow the shape of the housing.
Anyway, here's some pics to encourage you with your build I hope.
Park lights on.
Brake lights on.
At night with park lights on.
During the day with lights on to show illumination and visibility of metal behind lens