GRUB install to MBR

[Boo]

I have found that at the last part of the install questions: "where to put grub" is abit too simple or not simple enough (not enough options).
It already picks the boot disks MBR to install GRUB to but what if you have more than one disk or do not want GRUB installed to the MBR at all.
This may require an advanced options button/window or radio button location options for GRUB install.