Cisco CUCM: Upgrade Process From CUCM 8.5 To 10.5

I recently just did a Cisco CUCM upgrade from MCS servers running 8.5 to UCS servers running 10.5.1.  I thought I would generically outline the process I took to get there.

Moving 8.5.1-12900 CUCM production environment to the new 10.5.1 UCS BE7K environment.

• Install 8.5.1-10000 on a new virtual server on the UCS server.
• Upgrade from 8.5.1-10000 to 8.5.1-12900, so that this matches the current production environment.
• Take a backup of the current production environment, running 8.5.1-12900.
• Restore the backup to the UCS environment you did the upgrade on (on the UCS publisher). This has to be the exact same version of the production CUCM.
• Upgrade UCS 8.1.5 to UCSInstall_UCOS_8.6.2.25900-8.sgn.  
• Install ciscocm.version3-keys.cop.sgn file from 8.6 download to be able to upgrade to 10.5.1.
• Upgrade 8.6 to UCSInstall_UCOS_10.5.1.10000-7.sgn.
• Do a backup of 10.5.1 on the "upgraded" UCS virtual server.
• Install 10.5.1-10000-7 from scratch (which is the pre-loaded version that came on the UCS).
• Do a restore from the "upgraded" version on UCS to the new install on the UCS. 
• Add subscribers.