Converting 2003 & 2001 cyberfaces to 2000

Can someone tell me the rights proportions to convert 2003 & 2001 cyberfaces to 2000 ? I tried but i get too much distorted faces... I'm not a crack in Photoshop !
Cause it's not a matter of resampling with constrain proportions and cropping image it's harder !

If someone can explain that'll be great !

Thanks

Actually, i'm trying to convert faces of live 01 and 03 for my patchs and i haven't any problem