It's not an easy task to do, but I did complete it at lvl 73, with a lot of luck.
For the route to the Commander's room: enter the main building past the two guards, go straight forward, through the first room, over the moat and take a left.
That should bring you to the Rhino's Stables. No aggressive mobs there, surprisingly not even the rhino's there are aggressive, take the stairs all the way up and go left. At the first junction go right and follow straight ahead till you have to go right. You'll see the room way before you come to this point, two lvl 74's are guarding it, past them inside the room, take an instant left to get to the bed.
Be wary of the officer there that wanders, just wait till he gets far enough to use the little box under the bed and back away for a safe port out of there. (there's a spot in the corner out of all aggro reach)
It can be done, but I died twice as my FD's failed and even with about 9k hp, three blows are too much. Mobs start out at lvl 72 but increase rapidly to 74, haven't seen any that don't see through invis, or not at any important points anyway.
Is it worth it? Well, for those interested in getting these L&L's as fast as possible, sure.

