Quoted from MK6PIN:Glare from translite- The LCD doesn't reflect at all, but the translite is BRIGHT. There may be a brightness control for it ( kind of doubt it, but didn't have time to tinker much), but the glare on pf glass was pretty strong at the rear of the playfield.
Spike 1 games (GOT and GB) have a setting to turn down the backglass leds. I set mine to 25%, which basically removes all glare from the glass in a dark environment. I suspect BM66 will also have this setting inside the standard adjustments.