Quoted from Nelly:
The backglass shown here is the version they would use if they have to cut out the alpha displays due to cost. There is a second one in development which will include the display openings which will all be aligned along the bottom of the backglass. This second backglass will look just like this one, only with the addition of display openings. They are in the works on having a cost effective version of the alpha displays made. If it works out the backglass show here will not be needed. They are just trying to cover all their bases.
Scott said (in the podcast) that if they can get the costs on the numeric displays down (and he thinks they will), they are considering putting them below the BG, he references "Strange Science" as an example of a solution that would allow them to preserve most of the BG and still have the numeric displays.
This is okay, I can see the appeal as a relatively simple solution from an engineer's perspective, though I personally prefer the numeric displays to be embedded in the middle region of the BG, with mirrored outlines around it, like the Laser War example above.
Strangely enough, at the recent YegPin show in Edmonton I got a chance to play a buddy's Strange Science, interesting game to say the least. Ironically, his displays were wonky from making the trip and got progressively worse as the show went on. He ended up replacing them with LEDs from Nitro Amusements, who were also at the show. So, my point being, that recent experience, and now hearing that Scott is inspired by Strange Science's display placement feels like some kind of time/space looping going on already, which fits the theme of Total nuclear Annihilation perfectly.