Buttons in external swf load another external swf help

First I’d like to same I’m pretty new to actionscript so I’ve been trying to find examples of what I’m looking for. I found this tutorial here : http://www.kirupa.com/developer/mx2004/transitions.htm

This tutorial is close to what I’m looking to do but I’m not quite sure how to adapt it to what I want. I’m making a website that has external swfs that are being loaded. My main timeline has 2 empty movie clips. The top swf contains the buttons that I’d like to be able to click and load different swfs in the bottom empty movie clip. The tutorial above is close but the buttons are on the main timeline. I’m a beginner to actionscript and not quite sure how to change it so my buttons will load my swfs correctly.

I did some searching on here as well and found this : http://www.kirupa.com/forum/showthread.php?t=313763&highlight=multiple+loaded+swf+stage
This however is using an array which seems is too complicated for what I’m trying to do.

What I want to happen: When the site loads the top swf containing the buttons load and the bottom swf load. When different buttons are pushed in the top swf the corresponding bottom swf loads.

Any help would be greatly appreciated. Thanks.