FINALLY!!
I managed to get my system updated to Yosemite!!
I removed my SATA card, disconnected all drives, ran the Unibeast installer and chose my Mavericks boot drive (after making a clone, etc.) and it got stuck with 7 minutes remaining. I had the log up and it appeared to have gotten stuck at running the aclmodify.pl script.
Undaunted, I powered the computer down, then up again and chose the Unibeast stick. I ran the installer again, same way as before. This time it completed!
I then rebooted, ran Multibeast to install Chimera, sound, and network, and everything seems to be fine.
Persistence pays off. I knew that if others on this thread could do it, I could too.
So thankful to have all my apps and all my settings.
Booting is super fast.
Once the dust settles, I plan to switch to Clover and tinker with getting imessage working. But for now, it's time to enjoy family, friends, turkey, early Black Friday shopping, and all the other blessings this Thanksgiving day affords.
Thanks once again to Stork and to everyone who has contributed to this thread. So glad I chose this board and really happy I have successfully breathed new life into it today!
EDIT: Updated to 10.10.1 without incident.