I made this for my friend that had purchased the Relay Shield for the new Spark Core modules. The board fits in the enclosure with access to the screw terminals and also has places for light pipes (I used some PET / TGlass filament but clear PLA should work). There are also two small holes for access to the Spark Core reset and mode buttons.

Spark Core info: http://spark.io

Printed in PLA. The lid / top has holes and guide tubes that you can cut off pieces of clear PLA or PET filament (1.75mm) and insert into the tubes. Once the board is installed cut the filament to length so it sits flush with the top then put a dab of glue on the middle part of the filament to hold it in (be careful to not get glue on the ends of the filament "light pipe"). These will serve as light pipes so you can see the relay and core status along with power. You may have to carefully drill the holes out depending on your printer's resolution and detail. Place the board into the top then screw the bottom on using some small self tapping or plastic screws.