I'm going to answer this in case it would help anyone in the future. So the process I did was similar to what I outlined in my original post.  Except to save time, I simply shutdown the server, installed the RAID card, then booted up the server.  It recognized the RAID card, and installed the drivers automatically.  Since I had the 4 saved registry entries, I verified that they were created during the driver install, and in fact they were, even including the Start=0 allowing the OS to use the RAID card to boot from.  So, I didn't need to manually add those to the registry.  I then shut down the server again, and made the backup image.  I then installed the new drives, configured the RAID array, (after disconnected the original drive for safety), then booted and restored the image to the RAID array.  I then booted the server off the newly restore image to the RAID array, and everything came up just as if I'd booted from the original drive.  Since these drives were much larger, I then extended the partitions, and created one additional partition for data storage.   Bottom line, I'm glad I did the research, this could have been a disaster without the correct process.
I am helping a customer move from a single SATA hard drive to a pair of new enterprise-class drives to be configured in a RAID-1 array.  I want to image the existing drive, then restore the image to a newly created RAID array.  I know Windows won't boot if I do this without any pre-install driver setup.  Does anyone know the exact process to make this work?  I have excellent and dependable imaging software, and I've used it many times, so I'm cool with that part of it.  In my mind, this is what I would do, please help if you know of the proper process: 1.  Shutdown server and create the image to external USB drive. 2.  Add the PERC card and boot into Windows Server.  Add and/or let it detect the PERC card and add the drivers. 3.  Shutdown, install the new drives and cable assembly, boot to RAID BIOS, create the RAID-1 array, exit, restore image to RAID array. 4.  Boot Windows Server. -but will it boot at this point? I have located the LSI items in the registry on a different server that already has this exact configuration.  They are at HKLM\SYSTEM\CCS\services\LSI_XXX.  There are 4 separate branches, and one of them has a parameter of Start = 0.  Which I've figured out that this tells the OS it can start from this and boot.  Would I need to restore these items to the registry manually before I shutdown and create the RAID array, or will the driver installation do this for me?  I have exported and saved these 4 branches to .reg files. Thanks in advance for any guidance on this.
Adding Perc 6/iR to PE T310 and RAID1 to existing Server 2008 R2 with one SATA 
Drive