Well, being that FTFs are official software, where do you think you're going to find an FTF of software that doesn't exist?
There is no Xperia Z GPE, therefore there is no GPE software to flash to your phone.
custom roms are the way if ure interested in getting the google experience , unlikely to see a google edtion of the phone since its at least a year old but for z1ultra users this may be possible as there is a google edtion of the phone
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