Stage repositioning? Help, please

Ok,

So what I'm trying to do now is write a function (probably an onEnterFrame, unless you think it should just be called each time) that repositions and, if necessary, resizes movie clips. The catch is that the stage wont always be the main stage so Stage does not apply here. Right now I'm using the Loader component to house these movie clips, and later on they will be in their own swf.

That being said, what kind of function do you think would accomplish this? I need to be able to specify the stage width and height, like so:

something.function(param, param) {

}

Much appreciated…