Final shot first!

During the first test the protective plastic was left on and caused the acrylic to bubble. This was a spare piece of light guide acrylic which I ended up not liking as much as the standard clear cast acrylic.

For the second try the protective paper was removed and the job rerun. 

The finished piece looked great so the next step was a full 18" x 24" sheet.

I was able to fit nine pins, with one defect, I'm left with the eight needed for a single sheet. An extra sheet is on order to complete the sixteen total targets.

With a phone LED.