UnLoad previous .swf before Loading new .swf

I’m using the “Full Flash Site” Tutorial, and and trying to get the SWF files to fade in and out when they load, so that it isn’t so jumpy. I have gotten them to fade in properly, however, when I click the bottons to load the next .swf the old one disappears immediatly, and the new one fades in, causing an equally unattractive problem.

This Script appears on the black mc:

[AS]
onClipEvent(load) {

{
dir = 0;
speed = 6;
_alpha = 0;

}

this.dir = 1;

}

onClipEvent(unload) {

this.dir = -1;

}

onClipEvent(enterFrame)
{

    var temp1 = this._alpha + speed*dir;



    this._alpha = Math.min(100,Math.max(temp1,00));

}

[/AS]

Thanks in advance.