Well there is another less scruple-less way to get power armour.
I mentioned it before but I can expand on it, sneak up behind the person in power armour you want, pickpocket the power core, they will then get out of the power armour, now I think getting into the power armour will count as stealing it, however the model of a power armour is only based on the bits covering it not the internal frame.
And AFAIK it's only the internal frame that'll count as a stolen item, so you should be able to safely strip off the armour sections go back to one of your many T51 frames swap out the armour and hey presto brand new top of the line power armour
It's how I picked up T60 armour in the first hour of game play