Well, I can't promise anything (except that option 1 would be easier), but the basic steps to configure NTLoader to boot Fedora are...
- Confirm that your Fedora system is even capable of booting and running okay (a Super GRUB 2 Disk may be able to boot it).
- Force GRUB 2 to install its boot loader in the first sector of the Fedora boot partition (with Fedora booted, run grub2-install --force /dev/sdxy; you have to figure out x & y).
- Use the free and well-known utility BOOTPART to configure NTLoader to boot Fedora (more about that in the HOWTO, Method #2).
This is more likely to succeed if XP and Fedora are on the same hard drive. But in the end, this could turn out to be a lot of work for nothing. No promises.
P.S.: I would back up important things first. Also have the means and knowledge to restore the XP boot loader in case of a mishap with the grub2-install command.