Fedora 6 restore snafu

I'm hoping a seasoned Fedora Linux sysadmin has seen this before and
knows the path. I've Googled extensively & found several reports of the
same problem, but no solution. I have backed up & restored many Fedora
systems. I've had to deal with LVM UUID differences, reinstalling grub,
etc, but this one is kicking my butt.

My situation: I have a backup of a Fedora 6 system that I'm trying to
restore to the same system it came from. It attempts to boot, but stalls
with the message "can't find init (/sbin/init)".
When I edit the grub line and add the boot command "init = /bin/sh", I
get a very similar error complaining that it cant find init (/bin/sh).

This is all very similar to this post, which remains unsolved:
http://www.linuxquestions.org/questions/fedora-35/cant-clone-fc6-using-tar-backup-and-restore-506424/

What I've done:
1. Verify the listings in grub.conf and fstab are all correct.
2. Resinstall grub.
3. Disable selinux. Did that via /etc/selinux/config. I also touched an
.autorelabel file in the root of the hard drive.
4. Run fsck. It found & fixed some errors, no change in behavior.

What I can't do:
5. Rebuild the initrd. Can't, because when I run in linux rescue mode,
the "chroot /mnt/sysimage" command fails with the message "can't find
/bin/sh". Without chrooting, I can't get mkinitrd to work, and I can't
even get the initrd mounted on a loop device to inspect it. (I'm doing
this on another computer now.) I note that this problem is superficially
similar to the problem booting in the first place...

TIA. Paul

-- 
Paul Mackinney
2111ABC Etcheverry Hall
University of California at Berkeley
Berkeley, CA 94720-1740
510/643-0106
mackinney_at_berkeley.edu
--
Old age is the most unexpected of all things that happen to a man.
         --Leon Trotsky
 
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