If you do go with sliding doors, I wouldn't use the design millertime suggested. It's great with snake cages, but with an animal like a sav that's going to fling dirt into the tracks, the standard glass tracks like that just won't cut it. Opening the doors will become a challenge, and it will make some truly awful sounds.
For monitors (or any burrowing species that is going to throw dirt around) it's best to get wheeled glass tracks where the 'male' part of the tracks is on the bottom, unlike the standard tracks. They won't clog up with dirt this way.