Since the shell of the OLED model is the same size as the LCD one, the backplate should fit, and so should other external accessories. The buttons, too, since they're, well, the same dimensions. As for the main components like the Screen and Battery, the new OLED display won't work on the LCD variant since it now uses a different connector, not to mention different voltages. The battery, too, is thicker and won't accommodate the LCD variant because the LCD panel is thicker.