My advice to you:
1. Do this with a friend who has the same quest...so much easier! It took 3 tries for us to kill him until we figured out just one kites and the other attacks...rinse and repeat!
2. Fly in from SE bridge and stealth from there...easier as well.
3. Enjoy your Fear and Vengeance!
I'll probably never get the upgrades but I am quite happy with these....DPS jumped about 7k!