@ Stealth Expert,
With Throne of Bhaal installed, you still have more game to go!
What you are participating in is the end of the 'Shadows of Amn' part of the (original) game, and the 'Throne of Bhaal' expansion has only partly kicked in (with prior access to the Watcher's Keep dungeon).
Some strategic suggestions are
here on the confrontation you have after collecting and placing the Tears of Bhaal. It's far from an exhausted list of tactics however.
@ Illumina
Fair enough - I wasn't sure how sophisticated the UBB Code was in terms of embedding a link with the 'url=' command. I've fixed my post, but can't edit Duagloth Duskryn's post which quotes my original.