Help assigning instance names to external swf clip

Hi,

I’m trying to target the timeline of an externally loading movie but for some reason i’m unable to do that, any help would be greatfull

_level0.mainLoader_mc.instance237.emailFormHolder_mc.instance271
^^ ^^^^ ^^^^^^^
I would like to give this instance my own naming not the systems instance name,
this is how i’m calling the movie
mainLoader_mc.loadMovie(“official/mainContactsDisplay.swf”);

thank you