overwrite grub installed in MBR

I have installed two Linux distributions in my laptop , one is Linux Mint 12 and the other is Fedora 16.

Linux Mint’s grub has been installed in MBR ( /dev/sda )
Fedora’s grub has been installed in /dev/sda1 ( = /boot )

overwrite MBR’s grub with Fedora’s.

on Fedora , issue grub2-install

Fedora# grub2-install /dev/sda

After issuing grub2-install , Fefora’s grub will be installed in MBR ( in this case , /dev/sda )
You could boot both Fedora and Linux Mint after overwriting MBR’s grub with Fedora’s.