Preloaders

hi, just requestin some help!

Heres my setup

I have a flash file called main.swf which contains a content_mc and a menu_mc.

i am loading external swf’s into the content_mc. Which works fine…
I’m wanting to add a preloader (displaying preloader bar and percent) for each externally loaded swf.

What im wantin to know is where abouts i should have my preloader setup??

Should it be at the beginning of each external swf?

Inside the content_mc?

In main.swf?

Iv read tutorials etc, and cant get anythin to work and now i have just confused myself!!
So i could also do with help on the actionscript for this too…

Any help would be much appreciated.

Thank you,

Neil