Using the usual guide. Also from what I understand all GSM versions of the M8 can be S-Off'd (at least that is what I remember reading somewhere).
-Unlocked boot loader using htcdev
-Firewater for S-Off
Also just removed the red text on boot using this.
Worked like a charm. Though you have to make sure you are on 1.54.401.10 to begin with. (Only to remove the red text. Not the unlocking / rooting / recovery / s-off part)
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