It depends on the game, the ones he is talking about are called 'Double Panel', like the LCD Zaxxon or Terror House: (Pretty sure the clam-shell flip games are just single LCD)http://www.handheldmuseum.com/Bandai/TerrorHouse.htmhttp://www.handheldmuseum.com/Bandai/ZaxxonLCD.htm
There's at least 5 different Double Panel games (each one linked to on the top of either of those pages above). Pretty sure they all have the 'glop' chip... Can those be uncovered easily enough to see the die? I think I have a beater version of Zaxxon I'd be willing to sacrifice, if I still have it... (Too much crap, I keep loosing track of what I have and what I've sold over the years... Must get an inventory system in place.
There's also ones like this:http://www.handheldmuseum.com/Bandai/PenguinLand.htm
with two LCD screens for head-to-head play
And then these crazy things:http://www.handheldmuseum.com/Bandai/Gundam.htm
with a second hinged LCD panel, so sometimes you playing panel #1, sometimes panel #2, and sometimes both panels stacked on top of each other...
The Tomy 3D games I think just use a single LCD with only half being visible in each eye. So you could emulate half the screen for 2D playback, and then just support Oculus Rift at somepoint...
[Edit] Yeah, patent for Tomy 3D games here:https://www.google.com/patents/US4561723
Shows the single LCD. So implementation of 2D emulation might be simple enough if we can figure out the chip.
And, Kevin, games on their way to you tomorrow:
Bandai Dokodemo Dorayaki Doraemon
Bandai Machine Man
CGL Earth Invaders
CGL Super Kong
Entex Select-a-Game with Space Invaders and Football carts
Gakken Dig Dug
Mego Mini-Vid Sea Battle (LCD)