Loading swfs depending on screen resolution

Hi, I have a quick question…
I had done a swf content for some major resolution …flash800.swf,flash1200.swf,flash1600.swf… I load a swf at first which detects the x resolution of a screen and then loads appropriate content …the problem is that tke decision-making swf loads that flash movie into itself , so I have to do the checking resolution swf the maximum width and height the same as in the biggest (flash1600.swf) movie loaded into it…that makes all my work meaningless…
Can anyone help me how to totally unload that first testing swf or dynamically set stage width and height of that swf ???

Cheers