We are currently producing Cyrano de Bergerac. I am wanting to construct a small balcony with stairs on a 4x8 castered platform for the balcony scene. My problem is this, though making a stable step unit and platform is certainly no problem...when we put an actor on top with the hole unit on a wagon we will have a safety issue due to the top-heavy nature; especially as this particular play (like many other romantic plays) has a young "stud" climb up the balcony. This of course will increases the danger of the unit falling. I need a way to secure the unit to the floor for the scene such that it is safe...but then whatever mechanism I use to attach it to the stage mustn't be too intrusive to sight-lines for obvious reasons. I'm sure some of you have dealt with this scenario...what are your suggestions?