To stop it spinning, I remove one side of the shroud, and on that side, I put a locknut onto a long M3 bolt, and wind that in until the lock nut tightens against the frame. now the shroud bolt on the other side will undo. leave the long bolt in place to aid re assembly.
The N7 is way easier to work on. the engine drops out in less than 5 mins, and no need to remove the exhaust.