You could always burn it to a USB stick and install from that.  That is what I am doing.  My NEW AlienWare Win7 build is 5.9Gbs.  My next one will be even bigger as I add more features and newer modifications.  My primary purpose here is to make an install disk that will work with my new MX-17 R3 laptop.  It seems that the AW Win7 ultimate disk doesn't have the drivers to install on my laptop.  I will be testing my build in a few minutes after I finish "burning" it to my 16G USB stick.