OP

Quoted from avanwinkle:

I hadn't considered the backglass like that, I was just assuming that artwork = game so switching one means switching the other. The only reason for the new lighting panel is to line up the lights and flashers with the new artwork, so if you're not changing the artwork you wouldn't need to change the panel either.
For gameplay, the new backglass/panel is definitely optional, so you can enjoy your mirrored glass no problem . The original backglass' Ogres Alley lights are paired with the playfield ones, so those will behave as expected on the new game. The only caveat is that I'm repurposing the Jackpot ladder and flasher addresses for the new backglass (highlights on the characters, the game logo, and Lionman!), so you'd see those lights doing stuff during gameplay. No material impact, just something to note. Flashers won't make a difference, but the jackpot lights will be showing things unrelated to the jackpot. During SOF emulation, of course, everything will behave exactly as you're used to.
(Note for others: the LCD display will show the current jackpot value during SOF emulation, to make up for the loss of the jackpot ladder on the backglass)