You need a 12mm offset wrench. Sort of looks like an S. The torque is about 25ft/ft
You can get a bolt somewhere in the car and practice. Torque it with the torque wrench, mark where the bolt stops and the use the hand offset wrench so you can get a feel. It is pretty tight when you use the the short wrench, but not extremely tight. You can also put a little of blue thread locker to be safer. I have done my volvos many times. No problem.