How to reinstall Grub after a win install ?

Wed Apr 28 08:00:48 UTC 2004

Hi,
For a test I had to install a window$ on my server, on a separate drive 
( but on the same ctl ).
Of course, now,  the boot loader is the BillGates'one.
As I previously used the megaraid driver , I couldn't make a FC1 boot disk.
Running the FC1 CD-1, I can go into rescue mode, and my "old" system is 
mounted on /mnt/sysimage.
I can acces /mnt/sysimage/boot
But now ?
Regards
Gaetan