Tell opensuse 11.0 where to install GRUB

hi all
i have 2 hard drives one internal the other external i have 11.0 live cd but i want grub to go to external how do i tell the installer where to install GRUB?

thanks theacerguy

Partitioning/Install Guide - openSUSE Forums

thats loads of help i need that to put 11.0 on my xhdd without stuffing the main system

thanks again, theacerguy