After disassembling a genuine unit, Karl was able to reverse engineer the six-packs to make them almost identical, even down to the non-slip film that covers the front to hide the text. Each six-pack requires two PCBs to function correctly. The first is the LED backplate, and the second is the switch backplate. The switch backplate houses four ALPS soft-press buttons, which provide a good tactile press to the unit for recall action. Each caption has two LEDs to ensure complete illumination of the caption.
 
The FO & CPT lenses are created from 3mm orange perspex, primed and painted black, laser engraved, and coated with a non-slip film. The film hides the text when the captions are off and provides a genuine feel. It also helps protect the text from wear. 
 
The STL build files can be found and downloaded in step 1 of the build guide for free.
 
Several options are available:
 
Complete DIY SET
2 Switch PCB's
2 LED PCBs
2 Lenses (FO & CPT) With non-slip film
 
1 Set of PCBs
1 Switch PCB
1 LED PCB
 
6 Pack Lenses with Film
2 Lenses FO & Capt ready to fit
 
6 Pac Lenses Without Film
2 Lenses FO & Capt without the film for those wanting simplicity. 
 
Please note: There are now two versions of the LED PCBs: Common anode or Common Cathode.
 
The common anode requires all the grounds to switch on or off. These are ideal for the Pokeys card, and Karl's Break Out Board (BOB), which utilizes output shift registers.
 
The common-ground version is for use with the Arduino, or Karl's BOB.