A few questions before I mofo & flash

I keep putting off the 5.1 OTA, so I want to make the leap soon before it's too late. But first:

1. In the past my flashing has always been based on good write-ups that people on XDA provide. I'm not really seeing a good comprehensive write-up for the Turbo, but I do see the Moto X noob guide by julesjam. Is this close enough? Is there something better?
   


2. Will the system write protection prevent me from restoring backups from TIBU? My plan is to manually back up everything, get mofo and dirty flash 4.4.4, then back up what I can with TIBU (mostly interested in MMS), then clean flash 4.4.4 or 5.1 and restore my TIBU data. Are there any pitfalls here?
   


3. Will I have a problem flashing a 5.1 img over a 4.4.4 img? I;m currently on 21.44.12 and the original Mofo thread states "Note that if you flash a system image it should be for the same version you are on. If you are on a Turbo version 21.44.12, you need to flash a system image designed for a Turbo 21.44.12. Mismatching versions may have unwanted side-effects."

Thanks for any help/input!