Hi jcks32ml!
You're lucky because I have a blog post about this,
http://www.motd.hu/?p=90 , unfortunatelly its hungarian, so you have to learn this language.
Just kidding!

So, just a quick overview in english:
I modified the anaconda installer. On the installer disk u cand find a file, called stage2.img
If u mount this image( mount -o loop -t squashfs stage2.img /mnt/iso ), u will find the following file, raid.py
Firstly u have to copy the content of the stage2.img to an another location(the mounted squashfs is read only). After you copied the content of the stage2.img to the another location, you can modify the raid.py
There is a defined function in this file in the 174th row called get_raid_min_members()
I modified the isRaid1() return value to 1 from 2
Here is en example:
def get_raid_min_members(raidlevel):
"""Return the minimum number of raid members required for raid level"""
if isRaid0(raidlevel):
return 2
elif isRaid1(raidlevel):
return 1
elif isRaid5(raidlevel):
return 3
elif isRaid6(raidlevel):
return 4
elif isRaid10(raidlevel):
return 4
else:
raise ValueError, "invalid raidlevel in get_raid_min_members"
I saved the file and i created a new stage2.img (mksquashfs . ~/stage2.img), for this u need the squashfs-tools package.
Copy all of the content of the installer disk to an anothe rlocation, replace the stage2.img with the custom created one, and created an iso file(mkisofs -o ~/fc7.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -J -R -V "Custom Fedora")
It's worked for me, I think you want to install fedora 10 and not fedora 7, u can try it with f10, i'm not quarantee it will work. Maybe, i'm almost sure there was lots of changes in the anaconda installer, i did it with fedora 7 about 4 years ago.
Dont forget, this is just a workaround, the best way if u buy a 2nd disk before the install.

I know in an emergency situation maybe this is not possible, thats was happened to me.