I am on a windows 8.1 machine with a boot order of cd, usb, and finally my windows 8.1 drive. I have been using Kali via a live CD/USB and am in love with Kali. Now i am trying to install it to an external bootable 2T USB drive. I have started by formating the entire 2T drive and booting from a kali live CD. and using the graphical install, i have been using the guided - use entire drive method, pointing to me USB external drive. I get through the entire installation, but when it comes to installing the Grub boot loader it always fails? Of course, if i skip this part of teh installation it finishes but when i go to boot from that drive the computer just seems to freeze on a blank screen.

Does anyone have any idea what is causing this fail? can someone point me to a step by step instruction for installing kali to an external bootable drive?