The Limited Edition version has two parts to the backbox area - a red transparent piece of plexiglass for the lower part, and a smaller than usual backglass for the upper part.
There are several pictures here to compare : https://pinside.com/pinball/machine/eight-ball-deluxe-limited-edition
If you need more info, you'll need to be more specific.
Maybe if you post a picture of what you have, it will be easier to understand what you are missing.